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?

Zoe is investigating the composition of substance a, an unknown substance. using chemical processes, she analyzes substance a and determines it is composed of sodium, oxygen, and hydrogen atoms in a ratio of 1 : 1 : 1. what is substance a? a. a compound b. an element c. a heterogeneous mixture d. a homogeneous mixture

All of the following are part of the biosphere except

Acrystal that absorvd water from air is (blank)a. aqueousb. homogenousc. hygroscopicd. efflorescent