In the Melanie's Styling Salon, the time to complete simple haircut is normally distributed with mean of 25 minutes and a standard deviation of 4 minutes. What percent of customers require less than 32 minutes for a simple haircut?
A. 95.99 percent
B. 99.45 percent
C. 97.72 percent
D. 45.99 percent
Explain and show your work of how you got the answer.