Agallon of paint can cover 400 square feet. to the nearest half gallon, find how much paint will be needed to paint two coats on the walls and ceiling of room that is 20 feet long, 18 feet wide and 8 feet high

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?