A crane is used to suspend an I-beam in place while welders attach it to the support beams. If the beam weighs 400 N and is held in place for 80 seconds, how much power did the crane exert on the
I-beam?
none. It didn't do any work
5W
32000 W
9.8 N

its c its is a mixture of gases

heats surface water up

blue light is scattered in different directions by the tiny molecules of air. blue is scattered more than other colours because it has a shorter distance to travel which results in smaller waves. this is why we see a blue sky most of the time.