Which is the value of this expression when m= and n=-5

If the value of cos330°is√3/2 then find cos 165°.

What is the ratio fraction form of 25: 9

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?