Which radioactive gas comes from the earth and sometimes can accumulate in houses or other buildings? a. fluorine b. chlorine c. argon d. radon

If an electric circuit is not grounded it is best to reach out and touch it to provide the ground a.true or b.false

An object dropped from cliff falls with a constant acceleration of 10 metre per second square find its speed of two seconds after it was dropped

In the united states, tornadoes generally occur because of the freezing of ocean water underwater earthquakes meeting of cool and warm air masses shifting of warm and cool ocean currents