Choose the correct proportions.

8, 3, 12, 2

a) 2:3 = 12:8
b) 2:3 = 8:12
c) 2:8 = 3:12
d) 2:8 = 12:3

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?