2. Suppose that a two-arm clinical trial is being designed to test if a new drug is equivalent to the existing drug in delaying terminally ill liver cancer patients. Suppose that two drugs will be considered to be equivalent if the difference in the proportions of subjects who survive at least 3 years after the surgery does not exceed 8% (0.08) (FDA requires 20% of the overall average as the equivalence limit). Each group received 40 subjects, the sample proportions for the existing and new treatment are 40% and 45%. Test the null hypothesis of non-equivalence at the 5% level.