A researcher claims that the variance of monthly return of two stocks (X and Y) are different. There is sufficient evidence that the month returns of two stocks are independent and normally distributed. The researcher collects 48 and 39 monthly returns for the two stocks. Sample variances of the two stocks are 23 and 10 respectively.

(a) What is the null hypothesis?

(b) What is the alternative hypothesis?

(c) What is the test statistic?

(d) What is the p-value for the test statistics?

(e) What should be the conclusion of the researcher at 5% level of significance?