Q4 A sample of 59 wealth-market mutual funds was chosen on February 1, 2016, and the average annual rate of return over the past 30 days was found to be 3.5 percent, and the sample standard deviation...

Extracted text: Q4 A sample of 59 wealth-market mutual funds was chosen on February 1, 2016, and the average annual rate of return over the past 30 days was found to be 3.5 percent, and the sample standard deviation was 0.537 percent. A year earlier, a sample of 65 wealth-market funds showed an average rate of return of 4.63 percent, and the sample standard deviation was 1.11 percent. Is it reasonable to conclude (at a=0.01) that wealth-market interest rates declined during 2015?