Exercise 4. The price of a non-dividend-paying stock is $19 and the price of a 3-month European call option on the stock with a strike price of $20 is $4. The price of a 3-month European put option with the same strike price is 3, the risk-free rate of interest is 10%.

What opportunities are there for an arbitrageur? Describe your arbitrage strategy using a table of cash flows and determine the arbitrage profit.