Consider an option on a non-dividend-paying stock when the stock price is $30, the exercise price is $31, the risk-free interest rate is 2.5%, the volatility is 35% per annum, and the time to maturity is 6 months. Using the BlackScholes option price formula, evaluate the price of this option, assuming that: (a) it is an European call option

(b) it is an American call option

(c) it is an European put option

(d) Verify that put-call parity holds