The measurements giving the percentages for 10 men and 10 women are showed in data Excercise6.5-11. A) Find 90% confidence interval for the mean of the difference in the percentages for the males. B) Find 90% confidence interval for the mean of the difference in the percentages for the females. C) Based on these percentages decreased? D) If possible, check whether each set of differences come from a normal distribution.