The average ticket price for a New York Yankees baseball game was $81.89 for the 2003 season. With the additional cost of parkin, food, drinks, and souvenirs, the average cost for a family of four to attend a game totaled $442.54. Assume the average cost of attendance for a family of four is normally distributed with standard deviation of $65.

a. What is the probability that a family of four will spend more than $400?
b. What is the probability that a family of four will spend between $400 and $500?