. Apple stock (ticker: AAPL) is currently trading at $180. Consider two different portfo- lios for constructing a long butterfly spread on AAPL: IIA: Portfolio A, Long Butterfly Spread Sell an at-the-money call option Sell an at-the-money put option Buy a put option with strike price $160 Buy a call option with strike price $200 IIB: Portfolio B, Long Butterfly Spread Sell 2 at-the-money call options Buy a call option with strike price $160 Buy a call option with strike price $200 All options are European and have an expiration date of 1 year. Assume the stock does not pay any dividends. Assume there is no arbitrage in the market. The continuously compounded annual risk-free interest rate r and volatility o are unknown. You decide to buy a butterfly spread using Portfolio B and sell a butterfly spread using Portfolio A: your position is IIB - IIA Find an expression for the cost of IIB IIA today, as a function of the continuously compounded annual risk-free interest rate r. 20e- 120e -20e 20(1-e") . Apple stock (ticker: AAPL) is currently trading at $180. Consider two different portfo- lios for constructing a long butterfly spread on AAPL: IIA: Portfolio A, Long Butterfly Spread Sell an at-the-money call option Sell an at-the-money put option Buy a put option with strike price $160 Buy a call option with strike price $200 IIB: Portfolio B, Long Butterfly Spread Sell 2 at-the-money call options Buy a call option with strike price $160 Buy a call option with strike price $200 All options are European and have an expiration date of 1 year. Assume the stock does not pay any dividends. Assume there is no arbitrage in the market. The continuously compounded annual risk-free interest rate r and volatility o are unknown. You decide to buy a butterfly spread using Portfolio B and sell a butterfly spread using Portfolio A: your position is IIB - IIA Find an expression for the cost of IIB IIA today, as a function of the continuously compounded annual risk-free interest rate r. 20e- 120e -20e 20(1-e")