Answer it correctly please. Explain . I will rate accordingly with multiple votes.

Suppose that drinking two standard (alcoholic) drinks increases reaction time by / = 2 seconds with o = 3 seconds. If we want to carry out a one-sided significance test with a = 0.05 and B = 0.20 (so power is 80%) what sample size is needed to detect this increase? Give your answer rounded to the nearest integer. O The necessary sample size is n = 15. O The necessary sample size is n = 18. The necessary sample size is n = 20