Application 5.7 What cholesterol levels are unhealthy for teen boys? High levels of cholesterol in the blood increase the risk of heart disease. For 14-year-old boys, the distribution of blood cholesterol is approximately normal with mean = 170 milligrams of cholesterol per deciliter of blood (mg/dl) and standard deviation = 30 mg/dl. Let X = the cholesterol level of a randomly selected 14-year-old boy. 1. Cholesterol levels above 240 mg/dl may require medical attention. Find and interpret P(X> 240). 2. People with cholesterol levels between 200 and 240 mg/dl are at considerable risk for heart disease. What percent of 14-year-old boys have blood cholesterol between 200 and 240 mg/dl? 3. What cholesterol level would place a 14-year-old boy at the 10th percentile of the distribution? I