A random sample of 225 exams score drawn from a large population of students has a mean of 60 and a sample standard deviation of 9.

1.a. Estimate the population mean with a confidence level of 95%.

1.b. Estimate the population mean with a confidence level of 98%.

Your final answers should be correct to 4 places after the decimal point.

2.a. For a confidence level of 95% assuming the same statistics find the sample size that would result in a margin of error of 1.5.

2.b. For a sample size of 225 find the level of confidence that would result in a margin of error of 1.5.

Your final answers should be correct to 3 places after the decimal point.