John buys a share of Singapore Airline for $20 and simultaneously sells a call option on that stock for $5. Therefore he pays a total of $15 for the portfolio. The exercise price of the call option is $18.Determine the expiration day profit/loss of Johns covered call position if the stock price finishes at $0, $15, $18 and $20, respectively. Draw a diagram to show his profit at $0, $15, $18 and $20