Ok so only need help wth these... what is 3(x-9) then what is it equvilent to and these r the options...
3(x)+9.
3(x)+3(9).
3(x) – 9.
3(x) – 3(9).
its timed but no rush please help though 20 points

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?