1: An investor believe that the variance of return of bank stock is higher than variance of return from oil stocks. A sample of 20 returns from bank stock has a sample variance of 52.30. A sample of 13 returns from oil shocks has a variance of 11.17. Explain whether the evidence from the samples supports the investors belief?

2: Briefly explain how it might be possible to increase the power of test without increasing the chance of type 1 error?