Which of the following statements is true? 1.Heat is transferred in solids by convection.
2.Both liquids and gases are fluids.
3.Temperature is the same as heat.
4.Objects moving through air don't experience friction.

Cathy is pedaling down a steep hill on her bicycle and wants to be able to coast up the next hill, which is 25 meters high, without pedaling. cathy and her bicycle have a mass of 75 kg. assuming her bicycle is 100% efficient, what would her speed have to be?