Most radiation exposure comes from natural sources. These so-called "natural sources" include Radon, Internal, Terrestrial, and Cosmic. Among that, Radon proves to be the largest source of radiation. Radon is a naturally occurring radioactive gas that comes from the breakdown of uranium.
The average speed of the football is 15 meters per second. Just divide both of the numbers by 4 :)
In the question "What is true for solar, wind, and geothermal energy?" The correct answer is that they are all renewable energy.
Solar energy is energy that comes from the heat from the sun.
Wind energy is the energy that is generated from the wind.
Geothermal energy energy is the energy that comes from the heat from the earth.
Change of position and time
