Consider the function f(x,y)=xy3y9x+27 on the region on or above y=x^2 and on or below y=12. A. Find the absolute minimum value: B. Find the points at which the absolute minimum value is attained. List your answers as points in the form (a,b). C. Find the absolute maximum value: D. Find the points at which the absolute maximum value is attained. List your answers as points in the form (a,b)