Find the indicated value of the function f(x,y) = 2x + 7y -5. f(2, - 2) Select the correct choice below and, if necessary, fill in the answer box to complete your choice. O A. f(2, - 2) = (Simplify your answer.) O B. f(2, - 2) is undefined.Sketch the graph of z = f(x,y) = x2 + y2. A Which of the following surface graphs represents f(x,y) = x x 2 + 27 O A. OB. O C. Y Y Y vAn electric charge is so distributed that the electric potential at all points on an imaginary surface is the same. Such a surface Is called an equipotential surface. Sketch the graph of the equipotential surface whose equation is 64x- + 25y + z = 1600. .. . Choose the correct graph below. O A. O B. O c. Z Z y y X X X