Areconnaissance plane flies 600 km away from it’s base at 200 km/hr. then flies back to its base at 300 km/hr. what’s the average speed?

When the earth was formed and cooled, why did nickel and iron end up in the center of the earth while basalt and granite ended up in the outer layers

What is the mass of 8 moles of sodium atoms

A40 kilogram skier starts at the top of a 12 meter high slope. at the bottom, she is travelling 10 meters per second. how much energy does she lose to friction