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A study was carried out to assess the effect of alcohol on pilots. Ten pilots performed a series of routine tasks at a simulated altitude of 25, 000 feet. Each pilot performed the tasks in a completely sober condition and then three days later the pilot repeated the tasks after drinking alcohol. The response variable is the time (in seconds) of appropriate performance of the tasks. Bigger times are better. The null hypothesis is that alcohol has no effect, and the alternative is that performance degrades after alcohol use. The data are provided below along with summaries. 900 546.6 351.0 195.6 233.3 210.9 230.5 (a) Explain the experimental design and state the reasons to use this design. (b) Carry out the appropriate 1 test. (c) Obtain a 95% condence interval for the difference in mean performance Imder the two conditions. What do you conclude about the hypothesis based on your condence interval