A popular consumer magazine gave the following information about annual premiums (in dollars) for 18 renewable life insurance policies with similar benefits. The sample mean was found to be $413.94 with a standard deviation of $102.88. Assume that annual premiums follow an approximate bell-shaped distribution. Find a 90% confidence interval for the population mean of all annual premiums for such life insurance policies.

Astudy was interested in determining if eating milk chocolate lowered someone's cholesterol levels.ten people's cholesterol was measured. then, each of these individuals were told to eat 100g of milk chocolate every day and to eat as they normally did. after two weeks, their cholesterol levels were measured again. is there evidence to support that their cholesterol levels went down? how should we write the alternative hypothesis? (mud = the population mean difference= before - after)a. ha: mud = 0b. ha: mud > 0c. ha: mud < 0d. ha: mud does not equal 0