College admissions administrators at a university are reevaluating their entrance requirements. They believe that the mean GPA for graduating high school seniors has increased dramatically over the last decade. They randomly sample 85 records of graduating seniors from 10 years ago (sample 1) and find an average GPA of 2.68. An independent random sample of 80 current graduating seniors yields an average GPA of 2.94. If the population variance of high school GPA is 0.2601, find a 95% confidence interval for the difference in population mean GPA over the last decade. a. (-0.46, -0.05) b. (-0.36, -0.16) C. (-0.29, -0.13) d (-0.42, -0.10) 2) Price gouging occurs when retailers use the unfortunate circumstances of others to charge exorbitant prices for needed products. This frequently occurs after a significant natural disaster. Suppose an area experiences a devastating hurricane and authorities suspect price gouging occurred. The average price for a gallon of milk in the area was $2.34 prior to the hurricane. If after the hurricane we sample 10 stores and find the average price is now $3.05 with a standard deviation of 98 cents, does it appear the average price of milk increased significantly after the hurricane? State the critical value (CV), test statistic (TS), and decision from the test. (Use a = 0.05.) a. CV = 2.262, TS = 0.72, fail to reject HO ) b. CV=-1.833, TS = 2.29, fail to reject HO C. CV= -2.262, TS = -0.72, fail to reject HO D CV= 1.833, TS = 2.29, reject HO