3.14 Find the SD:  Find the standard deviation of the distribution in the following situations. (Keep 1 decimal place.)

a) MENSA is an organization whose members have IQs in the top 2% of the population. IQs are normally distributed with mean 100, and the minimum IQ score required for admission to MENSA is 131.
b) Cholesterol levels for women aged 20 to 34 follow an approximately normal distribution with mean 187 milligrams per deciliter (mg/dl). Women with cholesterol levels above 219 mg/dl are considered to have high cholesterol and about 18.5% of women fall into this category.