High levels (> 240 mg/dl) of cholesterol may increase the risk of heart disease. The distribution of cholesterol in the blood among people of the same age and gender is approximately normal. Assume that for teenage boys, blood cholesterol levels are normally distributed with a mean of 170 mg/dL and a standard deviation of 30 mg/dL. Use R to help find the probabilities below. Show your work in your submission.
(1) What percent of teenage boys have high cholesterol levels
(2) We select a sample of n = 50 teenage boys. What is the probability that the sample mean will be less than or equal to 180 mg/dL?