Draw a diagram showing the variation of an investors profit and loss with the terminal stock price for a portfolio consisting of

(a) One share and a short position in one call option

(b) Three shares and a short position in two call options

(c) Two shares and a short position in three call options

(d) Two shares and a short position in four call options

In each case, assume that the call option has an exercise price equal to the current stock price.