How does using multiple sources help when studying a region?

Which theory suggested that the earth was once a signle supercontient that gradually that broke up into the contients that we know today

Which movement developed in the early 1900s and encouraged the nationalist spirit of africans throughout the world? a. african nationalist b. tribalism c. pan-africanism d. african union

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