Here are exchange rates (dollars per unit) for the British pound at the beginning of each of the last 4 years. Estimate the volatility of the British pound currency's movements Beginning of the Year British pound 1 $1.50 2 $1.49 3 $1.54 4 $1.47 a. 3.95% O b. 12% O c. 0% d. 1.50%