Consider a forward which gives the right and obligation to buy a stock at a fixed price K during a period [t1, t2]. Thus is if the option has not been exercised before t2, it must be exercised at t2. How will the price of this derivative compare to that of an ordinary forward? How will it compare to the price of a American call option exercisable across the period [t1, t2]? How would you carry out the practical pricing of this option?