It is May and a trader writes (sells) a September call option with a strike price of $20. The stock price is $18, and the option price is $2. The option is held until September and the stock price is $25 at this time. Calculate the payoff and the profit. Draw the diagram to illustrate the profit.

Now consider the case when the trader buys a call option. Everything else is the same. Calculate the payoff and the profit. Draw the diagram to illustrate the profit.