Sound waves move the most slowly through? solids liquids or gases

What properties of a moving object are used in determining the object's energy of motion

A51 kg woman skis down a hill and her kinetic energy is 9.96e4 j. what is her speed?

Consider lifting a box of mass m to a height h using two different methods: lifting the box directly or lifting the box using a pulley (as in the previous part). what is wd/wp, the ratio of the work done lifting the box directly to the work done lifting the box with a pulley?