18. I estimate the Indonesian stock market will decline in the next three months. I do not own shares, nor do I short sell stocks in Indonesia. With futures, how can I make speculation using this information? Briefly explain and illustrate the strategy with a diagram. b. With options, how can this speculation be done? Briefly explain and illustrate the strategy with a diagram. 19. Share price = $ 100, exercise price = $ 95, interest rate = 8%, timeframe = 180 days, standard deviation = 0.6. Calculate the option price using the Black Scholes formula