to work on this test. It is open book and notes, so no LockDown Browser is required. Question 14 3 pts For a random sample of 100 students the average textbook and supplies cost was $620 for one semester. Calculate a 99% confidence interval for the true mean cost for a semester's materials. Assume a population standard deviation of $25. Calculate the margin or error for this analysis rounded to the nearest cent (2 decimal places). Previous Next >