Hi tutors, i need help for the following questions:

QUESO 1 in an attempt to find the mean number of hours his tutorial classmates spent per dav preparing for tutorials, John collected data from 10 of his friends in the tutorial group and found that the sample mean is 2.4 hours with a sample standard deviation of 0.8 hours. However, a davr later he felt that the sample size is too small. So he collected data from another 5 of his friends and found that the sample mean is 2.0 hours with a sample standard deviation of 1.2 hours. Find the sample mean and sample standard deviation when these 2 sets of data are combined. Question 2 Suppose the rates of return {in as} over the past 6 veers for two mutual funds are as follows: la} Compute the sample mean and standard deviation of Fund A. lb] Compute the sample mean and standard deviation of Fund B. lc} Compute the coefcient of variation {CV} for Fund A and B. id] in practice, CV is often used as a measure of risk because it measures the variation of the returns relative to the mean return. Based on the computed CV in {c}, which fund do you think has a higher investment risk