question:
Many natural rock formations change color over time. In Utah, for example, iron oxidized and formed red, orange, and yellow rock. Which of the following is the cause of this change?

answer:
chemical weathering

question:
Which method could be used to separate a solution of table salt and water?

answer:
evaporation

question:
What two gases make up most of the Earth's atmosphere?

answer:
Oxygen and nitrogen

question:
Which resource is most likely found in large amounts in forest ecosystems?

answer:
wood