The file P12_18.xlsx contains the daily closing prices of Chevron stock for a one-year period. Round your answers to two decimal places, if necessary. a. Use the random walk model to forecast the closing price of this stock on the next trading day. b. You can be about 99.7% certain that the forecast made in part a will be off by no more than how many dollars?

1 Date 2 19-Apr-17 3 ar 20-Apr-17 4 21-Apr-17 an 5 24-Apr-17 6 25-Apr-17 7 26-Apr-17 8 27-Apr-17 e 28-Apr-17 10 1-May-17 11 2-May-17 12 3-May-17 13 4-May-17 14 5-May-17 15 8-May-17 16 9-May-17 17 10-May-17 18 11-May-17 19 12-May-17 20 15-May-17 21 16-May-17 22 17-May-17 23 18-May-17 24 19-May-17 25 22-May-17 26 23-May-17 27 24-May-17 28 25-May-17 29 26-May-17 30-May-17 31 31-May-17 32 1-Jun-17 33 2-Jun-17 34 5-Jun-17 35 67 Source Adjusted Close 100.21 100.83 100.84 101.84 102.61 101.99 101.40 102.58 101.83 101.30 102.60 100.77 101.71 102.56 101.03 102.39 102.11 101.87 102.73 103.11 101.68 102.14 103.45 103.06 103.21 103.16 102.08 101.70 101.06 100.50 101.27 100.14 100.22 101.17 Data 2-18 30 36 7-Jun-17 37 8-Jun-17 38 9-Jun-17 ir 39 12-Jun-17 40 13-Jun-17 41 14-Jun-17 42 15-Jun-17 43 16-Jun-17 e 44 19-Jun-17 45 20-Jun-17 46 21-Jun-17 47 22-Jun-17 48 23-Jun-17 49 26-Jun-17 50 27-Jun-17 51 28-Jun-17 52 29-Jun-17 53 30-Jun-17 54 3-Jul-17 55 5-Jul-17 56 6-Jul-17 57 7-Jul-17 58 10-Jul-17 59 11-Jul-17 60 12-Jul-17 61 13-Jul-17 62 14-Jul-17 63 17-Jul-17 64 18-Jul-17 19-Jul-17 66 20-Jul-17 67 21-Jul-17 68 24-Jul-17 69 25-Jul-17 70 26-ML-17 100.78 101.01 103.34 104.93 105.02 103.53 103.27 105.23 104.37 103.41 101.48 101.44 101.98 101.14 101.07 101.28 101.12 101.33 103.24 101.61 100.83 10055 100.07 100.15 100.90 101.13 101.43 101.21 100.73 101.45 101.62 100.28 100.23 101.38 102.09 2-1865 82 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 18 99 100 101 102 103 26-Jul-17 27-Jul-17 28-Jul-17 31-Jul-17 1-Aug-17 2-Aug-17 3-Aug-17 4-Aug-17 7-Aug-17 8-Aug-17 9-Aug-17 10-Aug-17 11-Aug-17 14-Aug-17 15-Aug-17 16-Aug-17 17-Aug-17 18-Aug-17 21-Aug-17 22-Aug-17 23-Aug-17 24-Aug-17 25-Aug-17 28-Aug-17 29-Aug-17 30-Aug-17 31-Aug-17 1-Sep-17 5-Sep-17 6-Sep-17 7-Sep-17 8-Sep-17 11-Sep-17 12-Sep-17 102.09 103.05 105.01 106.05 107.59 107.28 106.28 106.94 106.62 107.17 107.70 106.94 106.08 105.58 105.44 104.81 103.90 104.45 103.77 104.33 104.58 105.39 106.17 105.71 105.81 105.68 105.57 106.69 107.36 109.66 109.67 108.67 110.38 110.35 www 3 a o OO 0 0 104 13-Sep-17 105 14-Sep-17 106 15-Sep-17 107 18-Sep-17 1108 19-Sep-17 109 20-Sep-17 110 21-Sep-17 111 22-Sep-17 112 25-Sep-17 113 26-Sep-17 114 27-Sep-17 115 28-Sep-17 116 29-Sep-17 117 2-Oct-17 118 3-Oct-17 119 4-Oct-17 120 5-Oct-17 121 6-Oct-17 122 9-Oct-17 123 10-Oct-17 124 11-Oct-17 125 12-Oct-17 126 13-Oct-17 127 16-Oct-17 128 17-Oct-17 129 18-Oct-17 130 19-Oct-17 131 20-Oct-17 132 23-Oct-17 133 24-Oct-17 134 25-Oct-17 135 26-Oct-17 136 27-Oct-17 137 30-Oct-17 112.01 112.27 112.45 113.00 114.12 114.15 114.25 115.06 115.74 115.28 115.21 115.38 115.26 115.19 115.58 115.34 116.32 114.80 115.47 116.54 117.06 116.87 116.89 117.84 117.93 115.90 115.95 116.38 116.67 116.96 116.18 116.18 111.38 112.21 138 31-Oct-17 139 1-Nov-17 140 2-Nov-17 141 3-Nov-17 142 6-Nov-17 143 7-Nov-17 144 8-Nov-17 145 9-Nov-17 2 146 10-Nov-17 147 13-Nov-17 148 14-Nov-17 149 15-Nov-17 150 16-Nov-17 151 17-Nov-17 152 20-Nov-17 153 21-Nov-17 154 22-Nov-17 155 24-Nov-17 156 27-Nov-17 157 28-Nov-17 158 29-Nov-17 159 30-Nov-17 160 1-Dec-17 161 4-Dec-17 162 5-Dec-17 163 6-Dec-17 164 7-Dec-17 165 8-Dec-17 166 11-Dec-17 12-Dec-17 168 13-Dec-17 169 14-Dec-17 170 15-Dec-17 171 18-Dec-17 172 19-Dec-17 113.68 113.69 113.13 112.80 114.81 115.01 114.45 115.01 114.95 115.00 114.69 114.23 113.44 113.58 113.59 114.03 114.77 115.36 114.45 115.30 116.03 117.82 118.33 119.65 119.20 118.43 118.45 118.74 119.23 118.50 118.75 118.35 118.55 118.52 118.66 2-18167 174 173 20-Dec-17 21-Dec-17 175 22-Dec-17 an 176 26-Dec-17 an 177 27-Dec-17 178 28-Dec-17 179 29-Dec-17 180 2-Jan-18 e 181 3-Jan-18 182 4-Jan-18 183 5-Jan-18 184 8-Jan-18 185 9-Jan-18 186 10-Jan-18 187 11-Jan-18 188 12-Jan-18 189 16-Jan-18 190 17-Jan-18 191 18-Jan-18 192 19-Jan-18 193 22-Jan-18 194 23-Jan-18 195 24-Jan-18 196 25-Jan-18 197 26-Jan-18 198 29-Jan-18 199 30-Jan-18 200 31-Jan-18 201 1-Feb-18 2-Feb-18 203 5-Feb-18 204 6-Feb-18 205 7-Feb-18 206 8-Feb-18 207 9-Feb-18 119.70 123.59 123.75 124.74 124.31 124.34 123.96 126.32 127.24 126.85 126.64 127.26 126.58 127.39 131.26 132.28 130.71 131.06 130.29 130.01 131.25 129.73 130.09 129.36 129.90 127.21 124.00 124.11 124.33 117.41 111.51 116.03 114.15 111.19 112.38 -18202 208 12-Feb-18 209 13-Feb-18 210 14-Feb-18 211 15-Feb-18 212 16-Feb-18 213 20-Feb-18 214 21-Feb-18 215 22-Feb-18 216 23-Feb-18 217 26-Feb-18 218 27-Feb-18 219 28-Feb-18 220 1-Mar-18 221 2-Mar-18 222 5-Mar-18 223 6-Mar-18 224 7-Mar-18 225 8-Mar-18 226 9-Mar-18 227 12-Mar-18 228 13-Mar-18 229 14-Mar-18 230 15-Mar-18 231 16-Mar-18 232 19-Mar-18 233 20-Mar-18 234 21-Mar-18 235 22-Mar-18 236 23-Mar-18 237 26-Mar-18 238 27-Mar-18 239 28-Mar-18 240 29-Mar-18 241 2-Apr-18 242 3-Apr-18 112.86 112.17 112.51 112.53 112.14 110.98 109.06 109.89 112.59 114.60 113.61 111.92 112.04 111.64 113.15 113.65 113.84 113.35 117.22 116.79 116.46 115.13 115.58 115.40 113.89 114.50 117.04 113.70 112.98 115.35 114.66 112.10 114.04 112.24 114.83 + + 1242 an 246 3-Apr-18 243 4-Apr-18 ar 244 5-Apr-18 245 6-Apr-18 9-Apr-18 247 10-Apr-18 248 11-Apr-18 249 12-Apr-18 e 250 13-Apr-18 251 16-Apr-18 252 17-Apr-18 253 18-Apr-18 254 19-Apr-18 255 256 257 258 259 260 261 114.83 114.48 117.29 114.76 115.98 118.85 119.25 119.23 119.92 120.70 121.46 123.82 123.82 1 Date 2 19-Apr-17 3 ar 20-Apr-17 4 21-Apr-17 an 5 24-Apr-17 6 25-Apr-17 7 26-Apr-17 8 27-Apr-17 e 28-Apr-17 10 1-May-17 11 2-May-17 12 3-May-17 13 4-May-17 14 5-May-17 15 8-May-17 16 9-May-17 17 10-May-17 18 11-May-17 19 12-May-17 20 15-May-17 21 16-May-17 22 17-May-17 23 18-May-17 24 19-May-17 25 22-May-17 26 23-May-17 27 24-May-17 28 25-May-17 29 26-May-17 30-May-17 31 31-May-17 32 1-Jun-17 33 2-Jun-17 34 5-Jun-17 35 67 Source Adjusted Close 100.21 100.83 100.84 101.84 102.61 101.99 101.40 102.58 101.83 101.30 102.60 100.77 101.71 102.56 101.03 102.39 102.11 101.87 102.73 103.11 101.68 102.14 103.45 103.06 103.21 103.16 102.08 101.70 101.06 100.50 101.27 100.14 100.22 101.17 Data 2-18 30 36 7-Jun-17 37 8-Jun-17 38 9-Jun-17 ir 39 12-Jun-17 40 13-Jun-17 41 14-Jun-17 42 15-Jun-17 43 16-Jun-17 e 44 19-Jun-17 45 20-Jun-17 46 21-Jun-17 47 22-Jun-17 48 23-Jun-17 49 26-Jun-17 50 27-Jun-17 51 28-Jun-17 52 29-Jun-17 53 30-Jun-17 54 3-Jul-17 55 5-Jul-17 56 6-Jul-17 57 7-Jul-17 58 10-Jul-17 59 11-Jul-17 60 12-Jul-17 61 13-Jul-17 62 14-Jul-17 63 17-Jul-17 64 18-Jul-17 19-Jul-17 66 20-Jul-17 67 21-Jul-17 68 24-Jul-17 69 25-Jul-17 70 26-ML-17 100.78 101.01 103.34 104.93 105.02 103.53 103.27 105.23 104.37 103.41 101.48 101.44 101.98 101.14 101.07 101.28 101.12 101.33 103.24 101.61 100.83 10055 100.07 100.15 100.90 101.13 101.43 101.21 100.73 101.45 101.62 100.28 100.23 101.38 102.09 2-1865 82 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 18 99 100 101 102 103 26-Jul-17 27-Jul-17 28-Jul-17 31-Jul-17 1-Aug-17 2-Aug-17 3-Aug-17 4-Aug-17 7-Aug-17 8-Aug-17 9-Aug-17 10-Aug-17 11-Aug-17 14-Aug-17 15-Aug-17 16-Aug-17 17-Aug-17 18-Aug-17 21-Aug-17 22-Aug-17 23-Aug-17 24-Aug-17 25-Aug-17 28-Aug-17 29-Aug-17 30-Aug-17 31-Aug-17 1-Sep-17 5-Sep-17 6-Sep-17 7-Sep-17 8-Sep-17 11-Sep-17 12-Sep-17 102.09 103.05 105.01 106.05 107.59 107.28 106.28 106.94 106.62 107.17 107.70 106.94 106.08 105.58 105.44 104.81 103.90 104.45 103.77 104.33 104.58 105.39 106.17 105.71 105.81 105.68 105.57 106.69 107.36 109.66 109.67 108.67 110.38 110.35 www 3 a o OO 0 0 104 13-Sep-17 105 14-Sep-17 106 15-Sep-17 107 18-Sep-17 1108 19-Sep-17 109 20-Sep-17 110 21-Sep-17 111 22-Sep-17 112 25-Sep-17 113 26-Sep-17 114 27-Sep-17 115 28-Sep-17 116 29-Sep-17 117 2-Oct-17 118 3-Oct-17 119 4-Oct-17 120 5-Oct-17 121 6-Oct-17 122 9-Oct-17 123 10-Oct-17 124 11-Oct-17 125 12-Oct-17 126 13-Oct-17 127 16-Oct-17 128 17-Oct-17 129 18-Oct-17 130 19-Oct-17 131 20-Oct-17 132 23-Oct-17 133 24-Oct-17 134 25-Oct-17 135 26-Oct-17 136 27-Oct-17 137 30-Oct-17 112.01 112.27 112.45 113.00 114.12 114.15 114.25 115.06 115.74 115.28 115.21 115.38 115.26 115.19 115.58 115.34 116.32 114.80 115.47 116.54 117.06 116.87 116.89 117.84 117.93 115.90 115.95 116.38 116.67 116.96 116.18 116.18 111.38 112.21 138 31-Oct-17 139 1-Nov-17 140 2-Nov-17 141 3-Nov-17 142 6-Nov-17 143 7-Nov-17 144 8-Nov-17 145 9-Nov-17 2 146 10-Nov-17 147 13-Nov-17 148 14-Nov-17 149 15-Nov-17 150 16-Nov-17 151 17-Nov-17 152 20-Nov-17 153 21-Nov-17 154 22-Nov-17 155 24-Nov-17 156 27-Nov-17 157 28-Nov-17 158 29-Nov-17 159 30-Nov-17 160 1-Dec-17 161 4-Dec-17 162 5-Dec-17 163 6-Dec-17 164 7-Dec-17 165 8-Dec-17 166 11-Dec-17 12-Dec-17 168 13-Dec-17 169 14-Dec-17 170 15-Dec-17 171 18-Dec-17 172 19-Dec-17 113.68 113.69 113.13 112.80 114.81 115.01 114.45 115.01 114.95 115.00 114.69 114.23 113.44 113.58 113.59 114.03 114.77 115.36 114.45 115.30 116.03 117.82 118.33 119.65 119.20 118.43 118.45 118.74 119.23 118.50 118.75 118.35 118.55 118.52 118.66 2-18167 174 173 20-Dec-17 21-Dec-17 175 22-Dec-17 an 176 26-Dec-17 an 177 27-Dec-17 178 28-Dec-17 179 29-Dec-17 180 2-Jan-18 e 181 3-Jan-18 182 4-Jan-18 183 5-Jan-18 184 8-Jan-18 185 9-Jan-18 186 10-Jan-18 187 11-Jan-18 188 12-Jan-18 189 16-Jan-18 190 17-Jan-18 191 18-Jan-18 192 19-Jan-18 193 22-Jan-18 194 23-Jan-18 195 24-Jan-18 196 25-Jan-18 197 26-Jan-18 198 29-Jan-18 199 30-Jan-18 200 31-Jan-18 201 1-Feb-18 2-Feb-18 203 5-Feb-18 204 6-Feb-18 205 7-Feb-18 206 8-Feb-18 207 9-Feb-18 119.70 123.59 123.75 124.74 124.31 124.34 123.96 126.32 127.24 126.85 126.64 127.26 126.58 127.39 131.26 132.28 130.71 131.06 130.29 130.01 131.25 129.73 130.09 129.36 129.90 127.21 124.00 124.11 124.33 117.41 111.51 116.03 114.15 111.19 112.38 -18202 208 12-Feb-18 209 13-Feb-18 210 14-Feb-18 211 15-Feb-18 212 16-Feb-18 213 20-Feb-18 214 21-Feb-18 215 22-Feb-18 216 23-Feb-18 217 26-Feb-18 218 27-Feb-18 219 28-Feb-18 220 1-Mar-18 221 2-Mar-18 222 5-Mar-18 223 6-Mar-18 224 7-Mar-18 225 8-Mar-18 226 9-Mar-18 227 12-Mar-18 228 13-Mar-18 229 14-Mar-18 230 15-Mar-18 231 16-Mar-18 232 19-Mar-18 233 20-Mar-18 234 21-Mar-18 235 22-Mar-18 236 23-Mar-18 237 26-Mar-18 238 27-Mar-18 239 28-Mar-18 240 29-Mar-18 241 2-Apr-18 242 3-Apr-18 112.86 112.17 112.51 112.53 112.14 110.98 109.06 109.89 112.59 114.60 113.61 111.92 112.04 111.64 113.15 113.65 113.84 113.35 117.22 116.79 116.46 115.13 115.58 115.40 113.89 114.50 117.04 113.70 112.98 115.35 114.66 112.10 114.04 112.24 114.83 + + 1242 an 246 3-Apr-18 243 4-Apr-18 ar 244 5-Apr-18 245 6-Apr-18 9-Apr-18 247 10-Apr-18 248 11-Apr-18 249 12-Apr-18 e 250 13-Apr-18 251 16-Apr-18 252 17-Apr-18 253 18-Apr-18 254 19-Apr-18 255 256 257 258 259 260 261 114.83 114.48 117.29 114.76 115.98 118.85 119.25 119.23 119.92 120.70 121.46 123.82 123.82