(c) Use the Black-Scholes model to estimate the price of a European call option on a non-dividend paying stock when the stock price is 22, the strike price is 23, the risk-free interest rate is 4% per annum, the volatility is 20% per annum, and the time to maturity is 4 months. Estimate the put price for the same underlying with a strike price of 23. What assumptions underpin this model? (10 marks)