For a recent 41-year period, there were 5,469 major earthquakes; these are earthquakes
measuring at least 6.0 on the richter scale in the world (based on u. s. geological survey
data).
a

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?