Lisa Mendes and Brad Lee work in the sales department of an AT&T Wireless store. Lisa has been signing up an average of 37 new cell phone customers every month with a standard deviation of 26, while Brad signs up an average of 47 new customers with a standard deviation of 18. The store manager offers both Lisa and Brad a $90 incentive bonus if they can sign up more than 90 new customers in a month. Assume a normal distribution to answer the following questions.

What is the probability that Lisa will earn the $90 incentive bonus?