Question: You know percentage daily increases in value of stocks in ten randomly selected days at stock market.

10%, 16%, 5%, 10%, 12%, 8%, 4%, 6%, 5%, 4%.

We assume that the percentage daily increase in value is a random variable with a normal distribution.

(a) Test the hypothesis that the population mean of daily increases in value is greater than 7% using a significance level 0.05.

Test the hypothesis that the population dispersion of daily increases in value is less than 3% using a significance level 0.01.