A) Suppose that the confidence interval for the population mean of summer income of undergraduate fulltime students using a sample size of 50, confidence level of 0.9 is [7000,10000]. If you increase the confidence level to 0.95, all other things remaining the same. what will be the new confidence interval?
B) Using the above data, will you reject or “fail to reject” (accept) the null hypothesis that MU = 8000 at 0.05 level of significance? Yes or No (and a 15 word explanation.)