Problem: A European call option and put option on a stock both have a strike price of $50 and an expiration date in two months. Both sell for $5. The risk-free interest rate is 10% per annum, the current stock price is $55, and a $2 dividend is expected in one month.
Required:
1. Identify the arbitrage opportunity open to a trader.
2. What is the present value of the trader's profit?