Consider a six-month European call option on the spot price of gold, that is, an option to buy one once of gold in the spot market is six months. The strike price is $1 200, the six months futures price of gold is $1 240, the risk-free rate of interest is 5% per annum, and the volatility of the futures price is 20%. The option is the same as a six-month European option on six-month futures price. Calculate the value of this option