An experiment is planned in which we have a set of regressors X1 and one addition regressor X2 will be created with values 0 for subjects that get a control treatment and 1 for subjects that get the experimental treatment. Treatment assignment will be done at random, with half of the subjects getting the experimental treatment. The test for a treatment effect will be done at level = 0.05, and it desired to make the experiment large enough to have 90% power. An estimate of is required, and suppose that setting = 0.5 is reasonable. Use a sample size calculator such as that of Lenth (2006-2009) to determine the sample size if the smallest meaningful treatment effect is equal to 1.0. Repeat for effect sizes of 0.5 and 2.0