Consider the following two-player game: first, player 1 selects a number x, which must be greater than or equal to zero. player 2 observes x. then, simultaneously and independently, player 1 selects a number y1 and player 2 selects a number y2, at which point the game ends. player 1 1’s payoff is u1 = y1y2 +xy1 −y 2 1 −(x 3/3), and player 2’s payoff is u2 = −(y1 −y2) 2 . represent this game in the extensive form. calculate and report the subgame perfect equilibrium.