The distribution of red blood cell counts is different for men and women. For both, the distribution is approximately Normal. For men, the middle 95% range from 4.5 to 5.7 million cells per microliter and for women, the middle 95% have red blood cells counts between 3.9 and 5.0 million cells per microliter.

a. What is the mean and the standard deviation of red blood cell counts for men? Explain your reasoning.

b. What is the mean and the standard deviation of red blood cell counts for women? Explain your reasoning.

c. Which gender shows more variation in red blood cell counts? Support your answer with appropriate statistics.