An investment company knows that the rates of return on itsportfolios have a mean of 7.45 percent, with a standard deviationof 3.82 percent. The company selects a sample of 144 portfolios toanalyze. Assume the company has tens of thousands of portfolios.(Careful- \"percent\" is just a unit here!) You do NOT need to checkCLT here.
A. What is the probability that the mean of the sample issmaller than 7 percent?
B. What is the probability that the mean of the sample is largerthan 7.3 percent?
C. What is the probability that the mean of the sample isbetween 7.5 and 8.2 percent?
