The random sample shown below was selected from a normal distribution. 3.10:? I". 5.3 CI Complete parts a and b. a. Construct a 90% condence interval for the population mean u. [339 = 3.21} [Round to two decimal places as needed] b. Assume that sample meani and sample standard deviation s remain exactly the same as those voujust calculated but that are based on a sample ofn = 25 observations. Repeat part a. What is the effect of increasing the sample size on the width of the condence intervals? The condence interval is [ELED . {Round to two decimal places as needed.)