Assume that z = f(w), w = g(x,y), x= 2r - s', and y = res. If gx(2,1) = - 4, g,(2,1) = 2, f'(8) = - 3, and g(2,1) = 8, find the following. az ze and ar r = 1, 5=0 as r = 1, s=0 oz Calculate and r = 1, 5=0 as r = 1, s=0 oz = ar r = 1, 5 =0 az r = 1, s =0