QUESTION 3 Find the absolute maximum and absolute minimum values of the function f (x, y) + + on the closed half-disk Hint: the boundary Of this half-disk will consist Of two parts. QUESTION 4 Let f (x, y) 2:ry+y2. Find Che maximum and minimum values Of f subject to the constraint + 4y2 20. Be sure to specify the points at which the-k;e values are obtained. QUESTION 5 Let y, z) 4 '2!/2 + z2. Find the minimum value of f subject to the constraint :r + 2y + z 8.