You slide a coin across the floor, and observe that it slows down and eventually stops. a sensitive thermometer shows that its temperature increased. what can we conclude? (select all that apply.)

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.