3. State whether each of the following changes would make a confidence interval wider or narrower. Use the setting above for some context. (a) Changing from a 95% level of confidence to a 90% level of confidence. (Hint: Calculate * for n = 100 at 95% and then 90% confidence. What does decreasing the level of confidence do to the multiplier?) (b) Changing from a sample size of 100 to a sample size of 200. Hint: Compute the standard error using the two different sample sizes. What happens to the SE as n increases?) (c) Changing from a standard deviation of 1.5 inches to a standard deviation of 0.5 inches. (Hint: Compute and compare the SE in both cases with n = 100.)