PLEASE HELP: Explain how you can find the circumference (perimeter) of a circle given its area. (I will give u the brainliest)

Find the domain of the following expression: 1/(√x)-2

Write the percent as a fraction or mixed number in simplest form. 0.8%

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?