Gray Matter, a noted Sacramento brain surgeon, is trying to perfect a gene-implant technique that...

Gray Matter, a noted Sacramento brain surgeon, is trying to perfect a gene-implant technique that stands to improve people’s IQs. While lab mice generally take 20 seconds to

go through a standard maze, 30 mice in Matter’s lab had a mean completion time of 16.8

seconds, with a standard deviation of 4.2 seconds. You may assume normality as needed.

(a) Obtain 95% confidence limits for µ, the post-implant population mean. (b) Assume

the population standard deviation σ of the maze-completion time for Matter mice is well

approximated by the number 4.2 above. Calculate the sample size needed to obtain a 95%

confidence interval for µ with maximum allowable error E = .6.