Activity Frame . . . . . . . The cowmnaweu 1&gression equation for a model involving two independent variables and 10 observations follows. = 33.3549 + 0.7906x; + 0.5341z, a. Interpret b1 and by in this estimated regression equation (to 4 decimals). b = [ - select your answer - E by = - Select your answer - v b. Estimate when &1 = 180 and &3 = 310 (to 3 decimals)