A community college administrators would like to know how many credit hours on average, each student takes per quarter. A random sample of 250...

 A community college administrators would like to know how many credit hours on average, each student takes per quarter. A random sample of 250 students yields a mean of 14.1 credit hours per quarter with a standard deviation of 2.3 credit hours per quarter. Estimate the mean to within 0.1 hours at 95% reliability and assume the sample standard deviation provides a good estimate for the population standard deviation. How large a sample do they need?