Use the Chain Rule to compute du ds at s = 0, t = 1, where T = st, y = ssint, z = scost. 6 ( 1 ) = 03. [14 points] Consider the function f(x, y) = x4 + y + 8ry. CL a) [7 pts] Find all critical points of f. b) [7 pts] Classify all critical points as either a local maximum, local minimum or saddle point