The price of a stock at the maturity of an option is ST . All options mature on the same day T. If the x-axis depicts possible values of the stock on the maturity day (ST ) and the y-axis depicts the gross payoff of a portfolio on the last day (i.e. ignore cash inflows/cash outflows today), draw the payoff diagram of the following. (a) Long a call of exercise price K = 100, long one unit of the underlying stock. (b) Long a call of exercise price K = 100, long one unit of the underlying stock, long one unit of discount bond with FV = K. (c) Short one call with exercise price of K = 80, short another call with exercise price of K = 110.