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Q8. In a study of maximal aerobic capacity, 12 women were used as subjects, and one measurement that was made was blood plasma volume. The following data give their blood plasma volumes in liters: 3.15 2.99 2.77 3.12 2.45 3.85 2.99 3.87 4.06 2.94 3.53 3.20 Assume that these are observations of a normally distributed random variable X that has mean p: and standard deviation 0. a) Give the value of the point estimate of a. b) Determine a point estimate of o'. e) Find a 90% condence interval for ,u