Total plasma volume is important in determining the required plasma component in blood replacement therapy for a person undergoing surgery. Plasma volume is influenced by the overall health and physical activity of an individual. Suppose that a random sample of45male firefighters are tested and that they have a plasma volume sample mean ofx= 37.5 ml/kg(milliliters plasma per kilogram body weight). Assume that=7.10ml/kgfor the distribution of blood plasma.

When finding an 99% confidence interval, what is the critical value for confidence level? (Give your answer to two decimal places.)

z_c=

Find a 99% confidence interval for the population mean blood plasma volume in male firefighters. What is the margin of error? (Round your answers to two decimal places.)

lower limit

upper limit

margin of error

What conditions are necessary for your calculations? (Select all that apply.)

is known

is unknown

nis large

the distribution of weights is uniform

the distribution of weights is normal

Find the sample size necessary for a 99% confidence level with maximal margin of errorE=2.10for the mean plasma volume in male firefighters. (Round up to the nearest whole number.