Total plasma volume is important in determining the required plasma component in blood replacement theory for a person undergoing surgery. Plasma volume is influenced by the overall health and physical activity of an individual. Suppose that sample of some male firefighters are tested and that they have a plasma volume sample mean of = 36.5 ml/kg (milliliters of plasma per kilogram body weight). Assume that = 7.60 ml/kg for the distribution of blood plasma. Find the smallest sample size necessary for a 98% confidence level with maximal error estimate E = 3.1.

Answer
a. 29
b. 33
c. 37
d. 3
e. 6