The quantity z can be expressed as a function of a and y as follows: z - f(x, y). Now a and y are themselves functions of r and 0, as follows: x = g(r, 0) and y - h(r, 0). Suppose you know that g(1, 7/2) = -1, and h(1, 7/2) = 1. In addition, you are told that of 91 (-1, 1) - 7, 2 (1,1) - 1, (1, 7/2) - -6, 26 (1, 1/2) = -7, of (1, 1/2) = -7, oh (1, 1/2) = 0. 3z (1, 7 / 2) Find