The volume of clay used to build a cylindrical pillar with a height of 9 centimeters is 324π cubic centimeters. what is the area of the base of the pillar in square centimeters?

1. according to the internal revenue service, the mean tax refund for the year 2007 was $2,708. assume the standard deviation is $650 and that the amounts refunded follow a normal probability distribution. a. what percent of the refunds are more than $3,000? b. what percent of the refunds are more than $3,000 but less than $4,000? c. what percent of the refunds are less than $2,000?