If a designer measure a pond and determines that the length of the pond across is 400 feet wide, what is the length of the radius

Twice the sum of a number and 4 is equal to three times the difference of the number and 7. find the number.

The area of a circle is equal to 1 dm². find the radius of the circle.

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?