(This continues question 8.) Let Xi = x if subject i is assigned to treatment at level x. A simple regression model says that given the assignments, the response Yi of subject i is α +Xiβ +i, where α, β are scalar parameters and the i are IID with mean 0 and variance σ2. Does randomization justify the model? If the model is true, can you estimate the average response if all the subjects had been assigned to treatment at level 75? Explain.