I'm currently studying for a Statistics final, and I'm stuck at some problems. I'd appreciate any help I could get. Question #1 Determine the minimum sample size needed to estimate a population mean with a margin of error of 24 and a confidence level of 95%, if the population standard deviation is 234. n = ? Question #2 Professors seem to believe that students score better on exams on Tuesdays, Wednesdays, and Thursdays than on Mondays or Fridays. A sample of the number of A and B grades achieved by a class on various days, Monday through Friday, is 15, 18, 17, 22, 16. A test is made of the claim, at a significance level of 0.05, that A and B grades occur with equal frquency on all days. What is the test statistic? What is the critical value?