Three firms (players I, II, and III) put three items (one each) on the market and advertise them either on morning or evening TV. A firm advertises exactly once per day. If more than one firm advertises at the same time, the profits of the firms advertising simultaneously are zero. If exactly one firm advertises in the morning, its profit is $250. If exactly one firm advertises in the evening its profit is $550. Firms must make their advertising decisions simultaneously. a) [2 points] Write down the payoffs for various players in form of two matrices, one for each of the pure strategies for III. Explain your answers. b) [8 points] Find all the symmetric mixed Nash equilibria.