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3 (Harder) Jack's utility function is given by u(x, y1, y2) = y1/2 + xy1 - y1 - 3. Bobby's utility function is given by u(y1, y2) = -(y1 - y2)2. The game is played in the following manner. First, Jack selects a number x 2 0. Then, simultaneously and independently, Jack and Bobby select numbers y, and y2 respectively. Find the backward induction outcome of the game