Can I get help with these two questions?

Given the function, f(x, y) = x y2 - 4y' find each of the following. A) A vector in the direction of greatest rate of increase in fat the point (2, -1) . B) The greatest rate of increase in f at the point (2, -1) . C) A vector in the direction of greatest rate of decrease at (2, -1). D) The derivative of f (x, y) at the point (2, -1) in the direction of v =-3i + 5j2 . Given equation w=xy2 -- + yz , with x=r +6s, y=15 z =3r -2s 1 pts A) Set up the symbolic string of partial derivatives for 2 pts B) Use the multivariable chain rule to find -. Do not substitute the r and s functions for x, y,z. ar 2 pts C) Evaluate - ow ar at r =2, s=-1 Leave result in simplified but exact form (no decimals)