In a physical change the molcules Your

Atoms rearange to make a new substance that has different properties

Molecules reagage to change the appearce but has the same properties

Molecules come apart and creat new substances

What happens in a global convection cell

The star betelgeuse is about 600 light-years away. if it explodes tonight, a. we'll know because debris from the explosion will rain down on us from space.b. we'll know it immediately because it will be brighter than the full moon in the sky.c. we won't know about it until 600 years from now.d. none of the above.

A100-watt light bulb illuminates a solar cell. the electricity from the solar cell operates a water pump that delivers 1 watt of power. what is the efficiency of the system?