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Question 4: Consider the function f (r, y) = x (y + 1) around the point P(1, 3). A. What is the rate of change of fat P in the direction of the vector v = (1, 4)? B. What is the maximum rate of change of fat P: In what direction (given as a vector) does this or Question 5: Find and classify the critical points of f(x, y) = x3 - y3 - 12x + 3y as relative maxima, minima or saddle points. Question 6: Evaluate JJJ EV x2 + y2 dV, where E is the region that lies inside the cylinder x2 + y = 16 and between the planes z - -5 and z = 4