question below:

Find ar when r=3 and s = - 3 if w= (x+y+z) , x=r-s, y= cos (r+ s), z= sin (r+ s). aw ar Ir =3, s= - 3 (Simplify your answer.)Find the gradient of the function f(x,y) = 4y - 5x at the point (9.4). Then sketch the gradient and the level curve that passes through that point Vfl(9,4) =( )l +( )1 (Simplify your answer.) Which of the following shows the level curve with the gradient at the point (9,4)? OA. OB. oc. Find the derivative of the function at Po in the direction of A. f(X,y,z) = - 4 ex cos (yz), Po (0,0,0), A= - i+j+ 2k (DAD) (0,0,0) = (Type an exact answer, using radicals as needed.)