diff --git a/10_Deleting/Wine/Exercises.ipynb b/10_Deleting/Wine/Exercises.ipynb
index 09cc35c57..9bde6e972 100644
--- a/10_Deleting/Wine/Exercises.ipynb
+++ b/10_Deleting/Wine/Exercises.ipynb
@@ -176,7 +176,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "### Step 11.  Set the rows of the random numbers in the column"
+    "### Step 11.  Use random numbers you generated as an index and assign NaN value to each of cell."
    ]
   },
   {
@@ -208,7 +208,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "### Step 14. Print only the non-null values in alcohol"
+    "### Step 13. Delete the rows that contain missing values"
    ]
   },
   {
@@ -224,7 +224,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "### Step 13. Delete the rows that contain missing values"
+    "### Step 14. Print only the non-null values in alcohol"
    ]
   },
   {
@@ -236,6 +236,15 @@
    "outputs": [],
    "source": []
   },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": true
+   },
+   "outputs": [],
+   "source": []
+  },
   {
    "cell_type": "markdown",
    "metadata": {},
@@ -271,7 +280,7 @@
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python 2",
+   "display_name": "Python [default]",
    "language": "python",
    "name": "python2"
   },
@@ -285,7 +294,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython2",
-   "version": "2.7.11"
+   "version": "2.7.12"
   }
  },
  "nbformat": 4,
diff --git a/10_Deleting/Wine/Exercises_code_and_solutions.ipynb b/10_Deleting/Wine/Exercises_code_and_solutions.ipynb
index 188d7c8aa..74c5373c6 100644
--- a/10_Deleting/Wine/Exercises_code_and_solutions.ipynb
+++ b/10_Deleting/Wine/Exercises_code_and_solutions.ipynb
@@ -21,7 +21,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 72,
+   "execution_count": 2,
    "metadata": {
     "collapsed": false
    },
@@ -47,7 +47,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 86,
+   "execution_count": 3,
    "metadata": {
     "collapsed": false
    },
@@ -182,7 +182,7 @@
        "4  1450  "
       ]
      },
-     "execution_count": 86,
+     "execution_count": 3,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -203,7 +203,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 87,
+   "execution_count": 4,
    "metadata": {
     "collapsed": false
    },
@@ -289,7 +289,7 @@
        "4  14.20  1.76  15.2  112  3.39  1.97  6.75"
       ]
      },
-     "execution_count": 87,
+     "execution_count": 4,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -318,7 +318,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 88,
+   "execution_count": 5,
    "metadata": {
     "collapsed": false
    },
@@ -411,7 +411,7 @@
        "4             1.97  6.75  "
       ]
      },
-     "execution_count": 88,
+     "execution_count": 5,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -430,7 +430,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 89,
+   "execution_count": 6,
    "metadata": {
     "collapsed": false
    },
@@ -523,7 +523,7 @@
        "4             1.97  6.75  "
       ]
      },
-     "execution_count": 89,
+     "execution_count": 6,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -542,7 +542,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 90,
+   "execution_count": 7,
    "metadata": {
     "collapsed": false
    },
@@ -635,7 +635,7 @@
        "4             1.97  6.75  "
       ]
      },
-     "execution_count": 90,
+     "execution_count": 7,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -654,7 +654,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 91,
+   "execution_count": 8,
    "metadata": {
     "collapsed": false
    },
@@ -747,7 +747,7 @@
        "4             1.97  6.75  "
       ]
      },
-     "execution_count": 91,
+     "execution_count": 8,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -769,7 +769,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 92,
+   "execution_count": 9,
    "metadata": {
     "collapsed": false
    },
@@ -787,7 +787,7 @@
        "dtype: int64"
       ]
      },
-     "execution_count": 92,
+     "execution_count": 9,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -805,7 +805,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 93,
+   "execution_count": 10,
    "metadata": {
     "collapsed": false
    },
@@ -813,10 +813,10 @@
     {
      "data": {
       "text/plain": [
-       "array([6, 6, 7, 4, 9, 4, 0, 1, 0, 8])"
+       "array([2, 3, 0, 5, 0, 9, 4, 0, 7, 2])"
       ]
      },
-     "execution_count": 93,
+     "execution_count": 10,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -830,12 +830,12 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "### Step 11.  Set the rows of the random numbers in the column"
+    "### Step 11.  Use random numbers you generated as an index and assign NaN value to each of cell."
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 94,
+   "execution_count": 11,
    "metadata": {
     "collapsed": false
    },
@@ -870,7 +870,7 @@
        "    </tr>\n",
        "    <tr>\n",
        "      <th>1</th>\n",
-       "      <td>NaN</td>\n",
+       "      <td>10.00</td>\n",
        "      <td>2.36</td>\n",
        "      <td>18.6</td>\n",
        "      <td>101.0</td>\n",
@@ -880,7 +880,7 @@
        "    </tr>\n",
        "    <tr>\n",
        "      <th>2</th>\n",
-       "      <td>10.00</td>\n",
+       "      <td>NaN</td>\n",
        "      <td>1.95</td>\n",
        "      <td>16.8</td>\n",
        "      <td>100.0</td>\n",
@@ -890,7 +890,7 @@
        "    </tr>\n",
        "    <tr>\n",
        "      <th>3</th>\n",
-       "      <td>13.24</td>\n",
+       "      <td>NaN</td>\n",
        "      <td>2.59</td>\n",
        "      <td>21.0</td>\n",
        "      <td>100.0</td>\n",
@@ -910,7 +910,7 @@
        "    </tr>\n",
        "    <tr>\n",
        "      <th>5</th>\n",
-       "      <td>14.39</td>\n",
+       "      <td>NaN</td>\n",
        "      <td>1.87</td>\n",
        "      <td>14.6</td>\n",
        "      <td>96.0</td>\n",
@@ -920,7 +920,7 @@
        "    </tr>\n",
        "    <tr>\n",
        "      <th>6</th>\n",
-       "      <td>NaN</td>\n",
+       "      <td>14.06</td>\n",
        "      <td>2.15</td>\n",
        "      <td>17.6</td>\n",
        "      <td>121.0</td>\n",
@@ -940,7 +940,7 @@
        "    </tr>\n",
        "    <tr>\n",
        "      <th>8</th>\n",
-       "      <td>NaN</td>\n",
+       "      <td>13.86</td>\n",
        "      <td>1.35</td>\n",
        "      <td>16.0</td>\n",
        "      <td>98.0</td>\n",
@@ -965,14 +965,14 @@
       "text/plain": [
        "   alcohol  malic_acid  alcalinity_of_ash  magnesium  flavanoids  \\\n",
        "0      NaN        1.78               11.2      100.0        2.76   \n",
-       "1      NaN        2.36               18.6      101.0        3.24   \n",
-       "2    10.00        1.95               16.8      100.0        3.49   \n",
-       "3    13.24        2.59               21.0      100.0        2.69   \n",
+       "1    10.00        2.36               18.6      101.0        3.24   \n",
+       "2      NaN        1.95               16.8      100.0        3.49   \n",
+       "3      NaN        2.59               21.0      100.0        2.69   \n",
        "4      NaN        1.76               15.2      112.0        3.39   \n",
-       "5    14.39        1.87               14.6       96.0        2.52   \n",
-       "6      NaN        2.15               17.6      121.0        2.51   \n",
+       "5      NaN        1.87               14.6       96.0        2.52   \n",
+       "6    14.06        2.15               17.6      121.0        2.51   \n",
        "7      NaN        1.64               14.0       97.0        2.98   \n",
-       "8      NaN        1.35               16.0       98.0        3.15   \n",
+       "8    13.86        1.35               16.0       98.0        3.15   \n",
        "9      NaN        2.16               18.0      105.0        3.32   \n",
        "\n",
        "   proanthocyanins   hue  \n",
@@ -988,7 +988,7 @@
        "9             2.38  5.75  "
       ]
      },
-     "execution_count": 94,
+     "execution_count": 11,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -1007,7 +1007,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 95,
+   "execution_count": 12,
    "metadata": {
     "collapsed": false
    },
@@ -1025,7 +1025,7 @@
        "dtype: int64"
       ]
      },
-     "execution_count": 95,
+     "execution_count": 12,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -1038,22 +1038,220 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "### Step 14. Print only the non-null values in alcohol"
+    "### Step 13. Delete the rows that contain missing values"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 108,
+   "execution_count": 13,
    "metadata": {
     "collapsed": false
    },
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<div>\n",
+       "<table border=\"1\" class=\"dataframe\">\n",
+       "  <thead>\n",
+       "    <tr style=\"text-align: right;\">\n",
+       "      <th></th>\n",
+       "      <th>alcohol</th>\n",
+       "      <th>malic_acid</th>\n",
+       "      <th>alcalinity_of_ash</th>\n",
+       "      <th>magnesium</th>\n",
+       "      <th>flavanoids</th>\n",
+       "      <th>proanthocyanins</th>\n",
+       "      <th>hue</th>\n",
+       "    </tr>\n",
+       "  </thead>\n",
+       "  <tbody>\n",
+       "    <tr>\n",
+       "      <th>1</th>\n",
+       "      <td>10.00</td>\n",
+       "      <td>2.36</td>\n",
+       "      <td>18.6</td>\n",
+       "      <td>101.0</td>\n",
+       "      <td>3.24</td>\n",
+       "      <td>2.81</td>\n",
+       "      <td>5.68</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>6</th>\n",
+       "      <td>14.06</td>\n",
+       "      <td>2.15</td>\n",
+       "      <td>17.6</td>\n",
+       "      <td>121.0</td>\n",
+       "      <td>2.51</td>\n",
+       "      <td>1.25</td>\n",
+       "      <td>5.05</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>8</th>\n",
+       "      <td>13.86</td>\n",
+       "      <td>1.35</td>\n",
+       "      <td>16.0</td>\n",
+       "      <td>98.0</td>\n",
+       "      <td>3.15</td>\n",
+       "      <td>1.85</td>\n",
+       "      <td>7.22</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>10</th>\n",
+       "      <td>14.12</td>\n",
+       "      <td>1.48</td>\n",
+       "      <td>16.8</td>\n",
+       "      <td>95.0</td>\n",
+       "      <td>2.43</td>\n",
+       "      <td>1.57</td>\n",
+       "      <td>5.00</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>11</th>\n",
+       "      <td>13.75</td>\n",
+       "      <td>1.73</td>\n",
+       "      <td>16.0</td>\n",
+       "      <td>89.0</td>\n",
+       "      <td>2.76</td>\n",
+       "      <td>1.81</td>\n",
+       "      <td>5.60</td>\n",
+       "    </tr>\n",
+       "  </tbody>\n",
+       "</table>\n",
+       "</div>"
+      ],
+      "text/plain": [
+       "    alcohol  malic_acid  alcalinity_of_ash  magnesium  flavanoids  \\\n",
+       "1     10.00        2.36               18.6      101.0        3.24   \n",
+       "6     14.06        2.15               17.6      121.0        2.51   \n",
+       "8     13.86        1.35               16.0       98.0        3.15   \n",
+       "10    14.12        1.48               16.8       95.0        2.43   \n",
+       "11    13.75        1.73               16.0       89.0        2.76   \n",
+       "\n",
+       "    proanthocyanins   hue  \n",
+       "1              2.81  5.68  \n",
+       "6              1.25  5.05  \n",
+       "8              1.85  7.22  \n",
+       "10             1.57  5.00  \n",
+       "11             1.81  5.60  "
+      ]
+     },
+     "execution_count": 13,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "wine = wine.dropna(axis = 0, how = \"any\")\n",
+    "wine.head()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Step 14. Print only the non-null values in alcohol"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 14,
+   "metadata": {
+    "collapsed": false,
+    "scrolled": true
+   },
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "1      True\n",
+       "6      True\n",
+       "8      True\n",
+       "10     True\n",
+       "11     True\n",
+       "12     True\n",
+       "13     True\n",
+       "14     True\n",
+       "15     True\n",
+       "16     True\n",
+       "17     True\n",
+       "18     True\n",
+       "19     True\n",
+       "20     True\n",
+       "21     True\n",
+       "22     True\n",
+       "23     True\n",
+       "24     True\n",
+       "25     True\n",
+       "26     True\n",
+       "27     True\n",
+       "28     True\n",
+       "29     True\n",
+       "30     True\n",
+       "31     True\n",
+       "32     True\n",
+       "33     True\n",
+       "34     True\n",
+       "35     True\n",
+       "36     True\n",
+       "       ... \n",
+       "147    True\n",
+       "148    True\n",
+       "149    True\n",
+       "150    True\n",
+       "151    True\n",
+       "152    True\n",
+       "153    True\n",
+       "154    True\n",
+       "155    True\n",
+       "156    True\n",
+       "157    True\n",
+       "158    True\n",
+       "159    True\n",
+       "160    True\n",
+       "161    True\n",
+       "162    True\n",
+       "163    True\n",
+       "164    True\n",
+       "165    True\n",
+       "166    True\n",
+       "167    True\n",
+       "168    True\n",
+       "169    True\n",
+       "170    True\n",
+       "171    True\n",
+       "172    True\n",
+       "173    True\n",
+       "174    True\n",
+       "175    True\n",
+       "176    True\n",
+       "Name: alcohol, dtype: bool"
+      ]
+     },
+     "execution_count": 14,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "mask = wine.alcohol.notnull()\n",
+    "mask"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 15,
+   "metadata": {
+    "collapsed": false,
+    "scrolled": true
+   },
    "outputs": [
     {
      "data": {
       "text/plain": [
-       "2      10.00\n",
-       "3      13.24\n",
-       "5      14.39\n",
+       "1      10.00\n",
+       "6      14.06\n",
+       "8      13.86\n",
        "10     14.12\n",
        "11     13.75\n",
        "12     14.75\n",
@@ -1115,130 +1313,15 @@
        "Name: alcohol, dtype: float64"
       ]
      },
-     "execution_count": 108,
+     "execution_count": 15,
      "metadata": {},
      "output_type": "execute_result"
     }
    ],
    "source": [
-    "mask = wine.alcohol.notnull()\n",
-    "mask\n",
-    "\n",
     "wine.alcohol[mask]"
    ]
   },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "### Step 13. Delete the rows that contain missing values"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 109,
-   "metadata": {
-    "collapsed": false
-   },
-   "outputs": [
-    {
-     "data": {
-      "text/html": [
-       "<div>\n",
-       "<table border=\"1\" class=\"dataframe\">\n",
-       "  <thead>\n",
-       "    <tr style=\"text-align: right;\">\n",
-       "      <th></th>\n",
-       "      <th>alcohol</th>\n",
-       "      <th>malic_acid</th>\n",
-       "      <th>alcalinity_of_ash</th>\n",
-       "      <th>magnesium</th>\n",
-       "      <th>flavanoids</th>\n",
-       "      <th>proanthocyanins</th>\n",
-       "      <th>hue</th>\n",
-       "    </tr>\n",
-       "  </thead>\n",
-       "  <tbody>\n",
-       "    <tr>\n",
-       "      <th>2</th>\n",
-       "      <td>10.00</td>\n",
-       "      <td>1.95</td>\n",
-       "      <td>16.8</td>\n",
-       "      <td>100.0</td>\n",
-       "      <td>3.49</td>\n",
-       "      <td>2.18</td>\n",
-       "      <td>7.80</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>3</th>\n",
-       "      <td>13.24</td>\n",
-       "      <td>2.59</td>\n",
-       "      <td>21.0</td>\n",
-       "      <td>100.0</td>\n",
-       "      <td>2.69</td>\n",
-       "      <td>1.82</td>\n",
-       "      <td>4.32</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>5</th>\n",
-       "      <td>14.39</td>\n",
-       "      <td>1.87</td>\n",
-       "      <td>14.6</td>\n",
-       "      <td>96.0</td>\n",
-       "      <td>2.52</td>\n",
-       "      <td>1.98</td>\n",
-       "      <td>5.25</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>10</th>\n",
-       "      <td>14.12</td>\n",
-       "      <td>1.48</td>\n",
-       "      <td>16.8</td>\n",
-       "      <td>95.0</td>\n",
-       "      <td>2.43</td>\n",
-       "      <td>1.57</td>\n",
-       "      <td>5.00</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>11</th>\n",
-       "      <td>13.75</td>\n",
-       "      <td>1.73</td>\n",
-       "      <td>16.0</td>\n",
-       "      <td>89.0</td>\n",
-       "      <td>2.76</td>\n",
-       "      <td>1.81</td>\n",
-       "      <td>5.60</td>\n",
-       "    </tr>\n",
-       "  </tbody>\n",
-       "</table>\n",
-       "</div>"
-      ],
-      "text/plain": [
-       "    alcohol  malic_acid  alcalinity_of_ash  magnesium  flavanoids  \\\n",
-       "2     10.00        1.95               16.8      100.0        3.49   \n",
-       "3     13.24        2.59               21.0      100.0        2.69   \n",
-       "5     14.39        1.87               14.6       96.0        2.52   \n",
-       "10    14.12        1.48               16.8       95.0        2.43   \n",
-       "11    13.75        1.73               16.0       89.0        2.76   \n",
-       "\n",
-       "    proanthocyanins   hue  \n",
-       "2              2.18  7.80  \n",
-       "3              1.82  4.32  \n",
-       "5              1.98  5.25  \n",
-       "10             1.57  5.00  \n",
-       "11             1.81  5.60  "
-      ]
-     },
-     "execution_count": 109,
-     "metadata": {},
-     "output_type": "execute_result"
-    }
-   ],
-   "source": [
-    "wine = wine.dropna(axis = 0, how = \"any\")\n",
-    "wine.head()"
-   ]
-  },
   {
    "cell_type": "markdown",
    "metadata": {},
@@ -1248,7 +1331,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 110,
+   "execution_count": 16,
    "metadata": {
     "collapsed": false
    },
@@ -1274,32 +1357,32 @@
        "    <tr>\n",
        "      <th>0</th>\n",
        "      <td>10.00</td>\n",
-       "      <td>1.95</td>\n",
-       "      <td>16.8</td>\n",
-       "      <td>100.0</td>\n",
-       "      <td>3.49</td>\n",
-       "      <td>2.18</td>\n",
-       "      <td>7.80</td>\n",
+       "      <td>2.36</td>\n",
+       "      <td>18.6</td>\n",
+       "      <td>101.0</td>\n",
+       "      <td>3.24</td>\n",
+       "      <td>2.81</td>\n",
+       "      <td>5.68</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>1</th>\n",
-       "      <td>13.24</td>\n",
-       "      <td>2.59</td>\n",
-       "      <td>21.0</td>\n",
-       "      <td>100.0</td>\n",
-       "      <td>2.69</td>\n",
-       "      <td>1.82</td>\n",
-       "      <td>4.32</td>\n",
+       "      <td>14.06</td>\n",
+       "      <td>2.15</td>\n",
+       "      <td>17.6</td>\n",
+       "      <td>121.0</td>\n",
+       "      <td>2.51</td>\n",
+       "      <td>1.25</td>\n",
+       "      <td>5.05</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>2</th>\n",
-       "      <td>14.39</td>\n",
-       "      <td>1.87</td>\n",
-       "      <td>14.6</td>\n",
-       "      <td>96.0</td>\n",
-       "      <td>2.52</td>\n",
-       "      <td>1.98</td>\n",
-       "      <td>5.25</td>\n",
+       "      <td>13.86</td>\n",
+       "      <td>1.35</td>\n",
+       "      <td>16.0</td>\n",
+       "      <td>98.0</td>\n",
+       "      <td>3.15</td>\n",
+       "      <td>1.85</td>\n",
+       "      <td>7.22</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>3</th>\n",
@@ -1327,21 +1410,21 @@
       ],
       "text/plain": [
        "   alcohol  malic_acid  alcalinity_of_ash  magnesium  flavanoids  \\\n",
-       "0    10.00        1.95               16.8      100.0        3.49   \n",
-       "1    13.24        2.59               21.0      100.0        2.69   \n",
-       "2    14.39        1.87               14.6       96.0        2.52   \n",
+       "0    10.00        2.36               18.6      101.0        3.24   \n",
+       "1    14.06        2.15               17.6      121.0        2.51   \n",
+       "2    13.86        1.35               16.0       98.0        3.15   \n",
        "3    14.12        1.48               16.8       95.0        2.43   \n",
        "4    13.75        1.73               16.0       89.0        2.76   \n",
        "\n",
        "   proanthocyanins   hue  \n",
-       "0             2.18  7.80  \n",
-       "1             1.82  4.32  \n",
-       "2             1.98  5.25  \n",
+       "0             2.81  5.68  \n",
+       "1             1.25  5.05  \n",
+       "2             1.85  7.22  \n",
        "3             1.57  5.00  \n",
        "4             1.81  5.60  "
       ]
      },
-     "execution_count": 110,
+     "execution_count": 16,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -1369,8 +1452,9 @@
   }
  ],
  "metadata": {
+  "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python 2",
+   "display_name": "Python [default]",
    "language": "python",
    "name": "python2"
   },
@@ -1384,7 +1468,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython2",
-   "version": "2.7.11"
+   "version": "2.7.12"
   }
  },
  "nbformat": 4,
diff --git a/10_Deleting/Wine/Solutions.ipynb b/10_Deleting/Wine/Solutions.ipynb
index 0e76021c5..df9b41387 100644
--- a/10_Deleting/Wine/Solutions.ipynb
+++ b/10_Deleting/Wine/Solutions.ipynb
@@ -21,15 +21,12 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 72,
+   "execution_count": 2,
    "metadata": {
     "collapsed": false
    },
    "outputs": [],
-   "source": [
-    "import pandas as pd\n",
-    "import numpy as np"
-   ]
+   "source": []
   },
   {
    "cell_type": "markdown",
@@ -47,7 +44,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 86,
+   "execution_count": 3,
    "metadata": {
     "collapsed": false
    },
@@ -182,7 +179,7 @@
        "4  1450  "
       ]
      },
-     "execution_count": 86,
+     "execution_count": 3,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -198,7 +195,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 87,
+   "execution_count": 4,
    "metadata": {
     "collapsed": false
    },
@@ -284,7 +281,7 @@
        "4  14.20  1.76  15.2  112  3.39  1.97  6.75"
       ]
      },
-     "execution_count": 87,
+     "execution_count": 4,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -309,7 +306,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 88,
+   "execution_count": 5,
    "metadata": {
     "collapsed": false
    },
@@ -402,7 +399,7 @@
        "4             1.97  6.75  "
       ]
      },
-     "execution_count": 88,
+     "execution_count": 5,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -418,7 +415,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 89,
+   "execution_count": 6,
    "metadata": {
     "collapsed": false
    },
@@ -511,7 +508,7 @@
        "4             1.97  6.75  "
       ]
      },
-     "execution_count": 89,
+     "execution_count": 6,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -527,7 +524,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 90,
+   "execution_count": 7,
    "metadata": {
     "collapsed": false
    },
@@ -620,7 +617,7 @@
        "4             1.97  6.75  "
       ]
      },
-     "execution_count": 90,
+     "execution_count": 7,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -636,7 +633,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 91,
+   "execution_count": 8,
    "metadata": {
     "collapsed": false
    },
@@ -729,7 +726,7 @@
        "4             1.97  6.75  "
       ]
      },
-     "execution_count": 91,
+     "execution_count": 8,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -745,7 +742,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 92,
+   "execution_count": 9,
    "metadata": {
     "collapsed": false
    },
@@ -763,7 +760,7 @@
        "dtype: int64"
       ]
      },
-     "execution_count": 92,
+     "execution_count": 9,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -779,7 +776,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 93,
+   "execution_count": 10,
    "metadata": {
     "collapsed": false
    },
@@ -787,28 +784,26 @@
     {
      "data": {
       "text/plain": [
-       "array([6, 6, 7, 4, 9, 4, 0, 1, 0, 8])"
+       "array([2, 3, 0, 5, 0, 9, 4, 0, 7, 2])"
       ]
      },
-     "execution_count": 93,
+     "execution_count": 10,
      "metadata": {},
      "output_type": "execute_result"
     }
    ],
-   "source": [
-    "# the number will be randoms, so yours will be different"
-   ]
+   "source": []
   },
   {
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "### Step 11.  Set the rows of the random numbers in the column"
+    "### Step 11.  Use random numbers you generated as an index and assign NaN value to each of cell."
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 94,
+   "execution_count": 11,
    "metadata": {
     "collapsed": false
    },
@@ -843,7 +838,7 @@
        "    </tr>\n",
        "    <tr>\n",
        "      <th>1</th>\n",
-       "      <td>NaN</td>\n",
+       "      <td>10.00</td>\n",
        "      <td>2.36</td>\n",
        "      <td>18.6</td>\n",
        "      <td>101.0</td>\n",
@@ -853,7 +848,7 @@
        "    </tr>\n",
        "    <tr>\n",
        "      <th>2</th>\n",
-       "      <td>10.00</td>\n",
+       "      <td>NaN</td>\n",
        "      <td>1.95</td>\n",
        "      <td>16.8</td>\n",
        "      <td>100.0</td>\n",
@@ -863,7 +858,7 @@
        "    </tr>\n",
        "    <tr>\n",
        "      <th>3</th>\n",
-       "      <td>13.24</td>\n",
+       "      <td>NaN</td>\n",
        "      <td>2.59</td>\n",
        "      <td>21.0</td>\n",
        "      <td>100.0</td>\n",
@@ -883,7 +878,7 @@
        "    </tr>\n",
        "    <tr>\n",
        "      <th>5</th>\n",
-       "      <td>14.39</td>\n",
+       "      <td>NaN</td>\n",
        "      <td>1.87</td>\n",
        "      <td>14.6</td>\n",
        "      <td>96.0</td>\n",
@@ -893,7 +888,7 @@
        "    </tr>\n",
        "    <tr>\n",
        "      <th>6</th>\n",
-       "      <td>NaN</td>\n",
+       "      <td>14.06</td>\n",
        "      <td>2.15</td>\n",
        "      <td>17.6</td>\n",
        "      <td>121.0</td>\n",
@@ -913,7 +908,7 @@
        "    </tr>\n",
        "    <tr>\n",
        "      <th>8</th>\n",
-       "      <td>NaN</td>\n",
+       "      <td>13.86</td>\n",
        "      <td>1.35</td>\n",
        "      <td>16.0</td>\n",
        "      <td>98.0</td>\n",
@@ -938,14 +933,14 @@
       "text/plain": [
        "   alcohol  malic_acid  alcalinity_of_ash  magnesium  flavanoids  \\\n",
        "0      NaN        1.78               11.2      100.0        2.76   \n",
-       "1      NaN        2.36               18.6      101.0        3.24   \n",
-       "2    10.00        1.95               16.8      100.0        3.49   \n",
-       "3    13.24        2.59               21.0      100.0        2.69   \n",
+       "1    10.00        2.36               18.6      101.0        3.24   \n",
+       "2      NaN        1.95               16.8      100.0        3.49   \n",
+       "3      NaN        2.59               21.0      100.0        2.69   \n",
        "4      NaN        1.76               15.2      112.0        3.39   \n",
-       "5    14.39        1.87               14.6       96.0        2.52   \n",
-       "6      NaN        2.15               17.6      121.0        2.51   \n",
+       "5      NaN        1.87               14.6       96.0        2.52   \n",
+       "6    14.06        2.15               17.6      121.0        2.51   \n",
        "7      NaN        1.64               14.0       97.0        2.98   \n",
-       "8      NaN        1.35               16.0       98.0        3.15   \n",
+       "8    13.86        1.35               16.0       98.0        3.15   \n",
        "9      NaN        2.16               18.0      105.0        3.32   \n",
        "\n",
        "   proanthocyanins   hue  \n",
@@ -961,14 +956,12 @@
        "9             2.38  5.75  "
       ]
      },
-     "execution_count": 94,
+     "execution_count": 11,
      "metadata": {},
      "output_type": "execute_result"
     }
    ],
-   "source": [
-    "# the number will be randoms, so yours will be different"
-   ]
+   "source": []
   },
   {
    "cell_type": "markdown",
@@ -979,7 +972,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 95,
+   "execution_count": 12,
    "metadata": {
     "collapsed": false
    },
@@ -997,15 +990,122 @@
        "dtype: int64"
       ]
      },
-     "execution_count": 95,
+     "execution_count": 12,
      "metadata": {},
      "output_type": "execute_result"
     }
    ],
+   "source": []
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
    "source": [
-    "# the number will be randoms, so yours will be different"
+    "### Step 13. Delete the rows that contain missing values"
    ]
   },
+  {
+   "cell_type": "code",
+   "execution_count": 13,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<div>\n",
+       "<table border=\"1\" class=\"dataframe\">\n",
+       "  <thead>\n",
+       "    <tr style=\"text-align: right;\">\n",
+       "      <th></th>\n",
+       "      <th>alcohol</th>\n",
+       "      <th>malic_acid</th>\n",
+       "      <th>alcalinity_of_ash</th>\n",
+       "      <th>magnesium</th>\n",
+       "      <th>flavanoids</th>\n",
+       "      <th>proanthocyanins</th>\n",
+       "      <th>hue</th>\n",
+       "    </tr>\n",
+       "  </thead>\n",
+       "  <tbody>\n",
+       "    <tr>\n",
+       "      <th>1</th>\n",
+       "      <td>10.00</td>\n",
+       "      <td>2.36</td>\n",
+       "      <td>18.6</td>\n",
+       "      <td>101.0</td>\n",
+       "      <td>3.24</td>\n",
+       "      <td>2.81</td>\n",
+       "      <td>5.68</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>6</th>\n",
+       "      <td>14.06</td>\n",
+       "      <td>2.15</td>\n",
+       "      <td>17.6</td>\n",
+       "      <td>121.0</td>\n",
+       "      <td>2.51</td>\n",
+       "      <td>1.25</td>\n",
+       "      <td>5.05</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>8</th>\n",
+       "      <td>13.86</td>\n",
+       "      <td>1.35</td>\n",
+       "      <td>16.0</td>\n",
+       "      <td>98.0</td>\n",
+       "      <td>3.15</td>\n",
+       "      <td>1.85</td>\n",
+       "      <td>7.22</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>10</th>\n",
+       "      <td>14.12</td>\n",
+       "      <td>1.48</td>\n",
+       "      <td>16.8</td>\n",
+       "      <td>95.0</td>\n",
+       "      <td>2.43</td>\n",
+       "      <td>1.57</td>\n",
+       "      <td>5.00</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>11</th>\n",
+       "      <td>13.75</td>\n",
+       "      <td>1.73</td>\n",
+       "      <td>16.0</td>\n",
+       "      <td>89.0</td>\n",
+       "      <td>2.76</td>\n",
+       "      <td>1.81</td>\n",
+       "      <td>5.60</td>\n",
+       "    </tr>\n",
+       "  </tbody>\n",
+       "</table>\n",
+       "</div>"
+      ],
+      "text/plain": [
+       "    alcohol  malic_acid  alcalinity_of_ash  magnesium  flavanoids  \\\n",
+       "1     10.00        2.36               18.6      101.0        3.24   \n",
+       "6     14.06        2.15               17.6      121.0        2.51   \n",
+       "8     13.86        1.35               16.0       98.0        3.15   \n",
+       "10    14.12        1.48               16.8       95.0        2.43   \n",
+       "11    13.75        1.73               16.0       89.0        2.76   \n",
+       "\n",
+       "    proanthocyanins   hue  \n",
+       "1              2.81  5.68  \n",
+       "6              1.25  5.05  \n",
+       "8              1.85  7.22  \n",
+       "10             1.57  5.00  \n",
+       "11             1.81  5.60  "
+      ]
+     },
+     "execution_count": 13,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": []
+  },
   {
    "cell_type": "markdown",
    "metadata": {},
@@ -1015,17 +1115,100 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 108,
+   "execution_count": 14,
    "metadata": {
-    "collapsed": false
+    "collapsed": false,
+    "scrolled": true
+   },
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "1      True\n",
+       "6      True\n",
+       "8      True\n",
+       "10     True\n",
+       "11     True\n",
+       "12     True\n",
+       "13     True\n",
+       "14     True\n",
+       "15     True\n",
+       "16     True\n",
+       "17     True\n",
+       "18     True\n",
+       "19     True\n",
+       "20     True\n",
+       "21     True\n",
+       "22     True\n",
+       "23     True\n",
+       "24     True\n",
+       "25     True\n",
+       "26     True\n",
+       "27     True\n",
+       "28     True\n",
+       "29     True\n",
+       "30     True\n",
+       "31     True\n",
+       "32     True\n",
+       "33     True\n",
+       "34     True\n",
+       "35     True\n",
+       "36     True\n",
+       "       ... \n",
+       "147    True\n",
+       "148    True\n",
+       "149    True\n",
+       "150    True\n",
+       "151    True\n",
+       "152    True\n",
+       "153    True\n",
+       "154    True\n",
+       "155    True\n",
+       "156    True\n",
+       "157    True\n",
+       "158    True\n",
+       "159    True\n",
+       "160    True\n",
+       "161    True\n",
+       "162    True\n",
+       "163    True\n",
+       "164    True\n",
+       "165    True\n",
+       "166    True\n",
+       "167    True\n",
+       "168    True\n",
+       "169    True\n",
+       "170    True\n",
+       "171    True\n",
+       "172    True\n",
+       "173    True\n",
+       "174    True\n",
+       "175    True\n",
+       "176    True\n",
+       "Name: alcohol, dtype: bool"
+      ]
+     },
+     "execution_count": 14,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": []
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 15,
+   "metadata": {
+    "collapsed": false,
+    "scrolled": true
    },
    "outputs": [
     {
      "data": {
       "text/plain": [
-       "2      10.00\n",
-       "3      13.24\n",
-       "5      14.39\n",
+       "1      10.00\n",
+       "6      14.06\n",
+       "8      13.86\n",
        "10     14.12\n",
        "11     13.75\n",
        "12     14.75\n",
@@ -1087,125 +1270,12 @@
        "Name: alcohol, dtype: float64"
       ]
      },
-     "execution_count": 108,
-     "metadata": {},
-     "output_type": "execute_result"
-    }
-   ],
-   "source": [
-    "# the number will be randoms, so yours will be different"
-   ]
-  },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "### Step 13. Delete the rows that contain missing values"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 109,
-   "metadata": {
-    "collapsed": false
-   },
-   "outputs": [
-    {
-     "data": {
-      "text/html": [
-       "<div>\n",
-       "<table border=\"1\" class=\"dataframe\">\n",
-       "  <thead>\n",
-       "    <tr style=\"text-align: right;\">\n",
-       "      <th></th>\n",
-       "      <th>alcohol</th>\n",
-       "      <th>malic_acid</th>\n",
-       "      <th>alcalinity_of_ash</th>\n",
-       "      <th>magnesium</th>\n",
-       "      <th>flavanoids</th>\n",
-       "      <th>proanthocyanins</th>\n",
-       "      <th>hue</th>\n",
-       "    </tr>\n",
-       "  </thead>\n",
-       "  <tbody>\n",
-       "    <tr>\n",
-       "      <th>2</th>\n",
-       "      <td>10.00</td>\n",
-       "      <td>1.95</td>\n",
-       "      <td>16.8</td>\n",
-       "      <td>100.0</td>\n",
-       "      <td>3.49</td>\n",
-       "      <td>2.18</td>\n",
-       "      <td>7.80</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>3</th>\n",
-       "      <td>13.24</td>\n",
-       "      <td>2.59</td>\n",
-       "      <td>21.0</td>\n",
-       "      <td>100.0</td>\n",
-       "      <td>2.69</td>\n",
-       "      <td>1.82</td>\n",
-       "      <td>4.32</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>5</th>\n",
-       "      <td>14.39</td>\n",
-       "      <td>1.87</td>\n",
-       "      <td>14.6</td>\n",
-       "      <td>96.0</td>\n",
-       "      <td>2.52</td>\n",
-       "      <td>1.98</td>\n",
-       "      <td>5.25</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>10</th>\n",
-       "      <td>14.12</td>\n",
-       "      <td>1.48</td>\n",
-       "      <td>16.8</td>\n",
-       "      <td>95.0</td>\n",
-       "      <td>2.43</td>\n",
-       "      <td>1.57</td>\n",
-       "      <td>5.00</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>11</th>\n",
-       "      <td>13.75</td>\n",
-       "      <td>1.73</td>\n",
-       "      <td>16.0</td>\n",
-       "      <td>89.0</td>\n",
-       "      <td>2.76</td>\n",
-       "      <td>1.81</td>\n",
-       "      <td>5.60</td>\n",
-       "    </tr>\n",
-       "  </tbody>\n",
-       "</table>\n",
-       "</div>"
-      ],
-      "text/plain": [
-       "    alcohol  malic_acid  alcalinity_of_ash  magnesium  flavanoids  \\\n",
-       "2     10.00        1.95               16.8      100.0        3.49   \n",
-       "3     13.24        2.59               21.0      100.0        2.69   \n",
-       "5     14.39        1.87               14.6       96.0        2.52   \n",
-       "10    14.12        1.48               16.8       95.0        2.43   \n",
-       "11    13.75        1.73               16.0       89.0        2.76   \n",
-       "\n",
-       "    proanthocyanins   hue  \n",
-       "2              2.18  7.80  \n",
-       "3              1.82  4.32  \n",
-       "5              1.98  5.25  \n",
-       "10             1.57  5.00  \n",
-       "11             1.81  5.60  "
-      ]
-     },
-     "execution_count": 109,
+     "execution_count": 15,
      "metadata": {},
      "output_type": "execute_result"
     }
    ],
-   "source": [
-    "# the number will be randoms, so yours will be different"
-   ]
+   "source": []
   },
   {
    "cell_type": "markdown",
@@ -1216,7 +1286,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 110,
+   "execution_count": 16,
    "metadata": {
     "collapsed": false
    },
@@ -1242,32 +1312,32 @@
        "    <tr>\n",
        "      <th>0</th>\n",
        "      <td>10.00</td>\n",
-       "      <td>1.95</td>\n",
-       "      <td>16.8</td>\n",
-       "      <td>100.0</td>\n",
-       "      <td>3.49</td>\n",
-       "      <td>2.18</td>\n",
-       "      <td>7.80</td>\n",
+       "      <td>2.36</td>\n",
+       "      <td>18.6</td>\n",
+       "      <td>101.0</td>\n",
+       "      <td>3.24</td>\n",
+       "      <td>2.81</td>\n",
+       "      <td>5.68</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>1</th>\n",
-       "      <td>13.24</td>\n",
-       "      <td>2.59</td>\n",
-       "      <td>21.0</td>\n",
-       "      <td>100.0</td>\n",
-       "      <td>2.69</td>\n",
-       "      <td>1.82</td>\n",
-       "      <td>4.32</td>\n",
+       "      <td>14.06</td>\n",
+       "      <td>2.15</td>\n",
+       "      <td>17.6</td>\n",
+       "      <td>121.0</td>\n",
+       "      <td>2.51</td>\n",
+       "      <td>1.25</td>\n",
+       "      <td>5.05</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>2</th>\n",
-       "      <td>14.39</td>\n",
-       "      <td>1.87</td>\n",
-       "      <td>14.6</td>\n",
-       "      <td>96.0</td>\n",
-       "      <td>2.52</td>\n",
-       "      <td>1.98</td>\n",
-       "      <td>5.25</td>\n",
+       "      <td>13.86</td>\n",
+       "      <td>1.35</td>\n",
+       "      <td>16.0</td>\n",
+       "      <td>98.0</td>\n",
+       "      <td>3.15</td>\n",
+       "      <td>1.85</td>\n",
+       "      <td>7.22</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>3</th>\n",
@@ -1295,21 +1365,21 @@
       ],
       "text/plain": [
        "   alcohol  malic_acid  alcalinity_of_ash  magnesium  flavanoids  \\\n",
-       "0    10.00        1.95               16.8      100.0        3.49   \n",
-       "1    13.24        2.59               21.0      100.0        2.69   \n",
-       "2    14.39        1.87               14.6       96.0        2.52   \n",
+       "0    10.00        2.36               18.6      101.0        3.24   \n",
+       "1    14.06        2.15               17.6      121.0        2.51   \n",
+       "2    13.86        1.35               16.0       98.0        3.15   \n",
        "3    14.12        1.48               16.8       95.0        2.43   \n",
        "4    13.75        1.73               16.0       89.0        2.76   \n",
        "\n",
        "   proanthocyanins   hue  \n",
-       "0             2.18  7.80  \n",
-       "1             1.82  4.32  \n",
-       "2             1.98  5.25  \n",
+       "0             2.81  5.68  \n",
+       "1             1.25  5.05  \n",
+       "2             1.85  7.22  \n",
        "3             1.57  5.00  \n",
        "4             1.81  5.60  "
       ]
      },
-     "execution_count": 110,
+     "execution_count": 16,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -1334,8 +1404,9 @@
   }
  ],
  "metadata": {
+  "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python 2",
+   "display_name": "Python [default]",
    "language": "python",
    "name": "python2"
   },
@@ -1349,7 +1420,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython2",
-   "version": "2.7.11"
+   "version": "2.7.12"
   }
  },
  "nbformat": 4,