Let Model 1 be the "unrestricted regression. If we want to perform an - test on the null hypothesis that the effect of 300 square feet on Iprice equals the effect of one more room, what variable (we'll name it "c") could you create in order to have STATA execute the correct restricted regression? C. c=sqft+300*room c=sqft+room C c=300*sqft+room C c=sqft+1/300*room c=300*sqft*room