the answer is 14.1%

Example 0.3.2. Consider a 4-month European call option on the British pound. Suppose that the current exchange rate is 1.60, the exercise price is 1.60, the risk-free interest rate in the United States is 8% per annum, the risk-free interest rate in Britain is 11% per annum, and the option price is 4.3 cents. Find the implied volatility. Proof: In the classroom Example 0.3.2. Consider a 4-month European call option on the British pound. Suppose that the current exchange rate is 1.60, the exercise price is 1.60, the risk-free interest rate in the United States is 8% per annum, the risk-free interest rate in Britain is 11% per annum, and the option price is 4.3 cents. Find the implied volatility. Proof: In the classroom