What formulas and setup are neeed and used for this radiation physics problem? Thanks!?

A digital cell phone emits 0.70 W of 2.9 MHz radio waves. Assume that it radiates uniformly What is the intensity of the electromagnetic wave at a distance of 15cm from the phone?

Comments on "What formulas and setup are neeed and used for this radiation physics problem? Thanks!?"
More: Integers,please help? Which macromolecules are copied and pass genetic information to the new cells? Skyventure? Long term side effects of hordenine? How to solve cos2x=sinx-2 in radians??