Mutual fund returns 2017, part 2.

An investment blog suggests that you’ve been doing this all wrong and should invest in mutual funds only for the short term. So you decide to compare returns at 1 month and 3 months.

a) Using the data provided, check the conditions for this test.

b) Write the null and alternative hypotheses for this test.

c) Test the hypothesis and find the P-value if appropriate.

d) Find a 95% confidence interval for the mean difference.