Problem 9. (10 points) Suppose that the price of a non-dividend-paying stock is $32, its volatility is 30% per annum, and the risk-free rate for all maturities is 5% per annum. Use Excel spreadsheet to calculate the price of the following option strategies. (a) A bear spread using European put options with strike prices of $25 and $30 and a maturity of six months. (b) A butterfly spread using European call options with strike prices of $25, $30, and $35 and a maturity of one year. (c) A strangle using European options with strike prices of $30 and $35 and a maturity of six months