Which event belongs in the missing box in the timeline above?

Write a short paragraph of about 150-300 words. explain how the physical environment can limit human activities.

Which numberline shows the solution to n -3

Which phrases describe oxygen's roles in earth’s atmosphere? check all that apply. allows fuels to burn forms clouds that produce rain is the gas that animals breathe is used by plants to produce food forms ozone that absorbs the sun's harmful rays