A doctor wants to estimate the HDL cholesterol of all 20-29 year old females. How many subjects are needed to estimate the HDL cholesterol within 4 points with 99% confidence assuming stdv=18.3? Suppose the doctorwould be content with 90%confidence. How does the decrease in confidence affect the sample size required?
A. 99% confident level requires ------- subjects
B. 90% confident level requires--------subjects