The mean and standard deviation of a random sample of n measurements are equal to 33.9 and 3.4, respectively.a. Find a 90% confidence interval for u if n = 100.b. Find a 90% confidence interval for u if n = 400.c. Find the widths of the confidence intervals found in parts a and b. What is the effect on the width of a confidence interval of quadrupling the sample size whileholding the confidence coefficient fixed?a. The 90% confidence interval for u if n = 100 is approximately O.(Round to three decimal places as needed.)