MY NO 5. [-/3 Points] DETAILS SCALCETS 14.5.021. Use the Chain Rule to find the indicated partial derivatives. z=x +xy, x=s+2t -4, y =stu"; dz z 02 when s = 3, t = 5, u = 2 ds' at' du dz 85 02 at Need Help? Watch It MY NO 6. [-/8 Points] DETAILS SCALCETS 14.5.052. Assume that all the given functions have continuous second-order partial derivatives. If z = f(x, y), where x = 5r cos(8) and y = 5r sin(@), find the following. dz ar dz dz ar ax (b) dz ae dz ae ay (c) ar de 8-z az + By dx ar de ax