If a wheelchair-marathon racer moving at 13.1 miles per hour expends energy at a rate of 655 calories per hour, how much energy in calories would be required to complete a marathon race
(26.2 miles) at this pace?

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