Acircle has its center at the origin, and (5, -12) is a point on the circle. how long is the radius of the circle?

How many days was the temperature above 90 degrees?

What is the result of adding the system of equations? 2x+y=4 3x-y=6

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?