need simple explain please

11) The following figures show the pay-off structure of stock op the expiration date. Circle the correct position (long or short) a) Long / Short Call / Put ! structure of stock options depending on possible stock prices at cet position (long or short) and type of the option (call or put) IK S7 b) Long Short Call / Put 12) Suppose that a European call option with a strike price of $75 costs $4 and is held until expiration. a) Under what circumstances will the call option be exercised? b) Under what circumstances the holder of the call option make a profit? 13) Suppose that a European put option to with a strike price of $70 costs $5 and is held until expiration. a) Under what circumstances will the put option be exercised? b) Under what circumstances the seller of the put option make a profit? An investor is looking for arbitrage opportunities in the Treasury bond futures market. He finds that the futures price is too low and he wants to lock in a riskless profit. State two issues on difficulty of arranging this arbitrage!(be specific and do NOT write excessively, the correct answer can be stated in one sentence for each issue)