(81) Consider a stock with current price $50, A 3-month European call option and a 3-month European put option are written on this stock with the same strike price $47. This stock is expected to pay dividend $5 after 3 months. The continuously compounded risk-free rate is 5%. The prices of these two options are $2. Is there any arbitrage opportunity? Why? (5pts) (b) Consider three 5-month European call options written on the same stock with strike prices of $45, $55, $70, respectively. Assume the prices of these three options are $2, $5, and $8, respectively. Is there any arbitrage opportunity? Why? (5pts)