This problem will give you practice in constructing confidence intervals and in discovering how to reduce their size (without sacrificing confidence). Smaller confidence intervals capture the value of more precisely. a. How wide is the 95% confidence interval about a population mean when = 4 and N = 4? b. How much smaller is the 95% confidence interval about a population mean when N is increased fourfold to 16 ( remains 4)? Samples, Sampling, Distributions, and Confidence Intervals 173 c. Compared to your answer in Part a, how much smaller is the 95% confidence interval about a population mean when N remains 4 and is reduced to 2