Name two things that reduce friction

What type of reaction is represented by the following example? 2co2 (g) + 4h2o (l) + 1452 kj 2ch3oh (l) (g) + 3o2 (g) exothermic endothermic

What causes different colors to appear in the sky? the absorption of light by air molecules the reflection of light by bodies of water the greenhouse effect in earth's atmosphere the scattering and reflection of light by dust particles

What four properties do all waves have in common