What does the atomic number respresent? (from my science homework)

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.

How much energy will be transferred to your eardrum while listening to this sound for 1.0 min?

Acar weighs 15,000 n, and its tires are inflated to a pressure of 190kpa. how large is the area of the car's tires that are in contact with the road?