To see how much of a difference time of day made on the speed at which he could download files, a college sophomore performed an experiment. He placed a file on a remote server and then proceeded to download it at three different time periods of the day. He downloaded the file 48 times in all, 16 times at each Time of Day, and recorded the Time in seconds that the download took,
a) State the null and alternative hypotheses, being careful to talk about download Time and Time of Day as well as parameters.

b) Perform an ANOVA on these data. What can you conclude?
c) Check the assumptions and conditions for an ANOVA. Do you have any concerns about the experimental de-sign or the analysis?
d) (Optional) Perform a multiple comparisons test to determine which times of day differ in terms of mean download time.

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Time (sec) Time of Day Time (sec) Early (7 a.m) 68 Early (7 a.m) 138 Early (7 a.m) 75 Early(7 a.m) 186 Early (7 a.m.) 68 Early (7 a.m.) Early (7 a.m.) 93 Early (7 a.m.) 90 Early (7 a.m.) 71 Early (7 a.m.) 154 Early (7 a.m) 166 Early (7 a.m)130 Early (7 a.m) 72 Early (7 a,m) 81 Early (7am) | 76 Early (7 a.m.) 129 Time of Day Evening (5 p.m.) 299 Evening (5 p.m.) 367 Evening (5 p.m) 331 Evening (5 p.m.) 257 Evening (5 p.m.) 260 Time (sec) Time of Day Late Night (12 a.m.) 216 Late Night (12 a.m.) 175 Late Night (12 am.) 274 Late Night (12 a.m.) 171 Late Night (12 a.m) 187 Late Night (12 a.m.) 213 Late Night (12 a.m) 221 Late Night (12 a.m.) 139 Late Night (12 a.m) 226 Late Night (12 am) 128 Late Night (12 a.m)236 Late Night (12 a.m) 128 Late Night (12 a.m) 217 Late Night (12 am.) 196 Late Night (12 a.m)201 Late Night (12 a.m., 161 217 Evening (5 p.m) 269 Evening (5 p.m.) 252 Evening (5 p.m.) 200 Evening (5 p.m) 296 Evening (5 p.m.) 204 Evening (5 p.m.) 190 Evening (5 p.m) 240 Evening (5 p.m.) 350 Evening (5 p.m.) 256 Evening (5 p.m.) 282 Evening (5 p.m.) 320