please I need help on 2 iii. and 2 iv. math analysis questions.

2. i. Carefully, graph the function f(x, y)=-3x-3y+2 on the first octant of a properly labeled coordinate system.ii. Use a ruler to generate a contour map for the function f(x, y) = Vx – y , using z=0, 1, and 2 .iii. Given f(x,y)=-3-2x’y log, (2x”4xy3 -2x? yfind f,(x, y) . (Do not simplify.)3-2x’ y 10g, ( 2×3)iv. Give a point (x, y) where the function f(x, y )=-cannot be evaluated, and state the reason.4xy3 – 2x’ y