I need help with this problem, can you explain step by step.

20. (15 points) Information for two independent samples from two populations is given as follows: n1 = 31,X1 = 28, 51 = 9 n2 = 41, X2 = 25, 52 = 8 (a) (5 points) Is there evidence to show that the two populations have different variance under significant level 10%? (b) (5 points) Under significant level 10%, test whether the mean of population 1 is greater than population 2. Draw your conclusion. (c) (5 points) Construct a one-tail confidence interval with lower bound for the difference of population means under confidence level 90%. Compare your results with part (b) and draw your conclusion