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Barry is applying the principles of relative dating to a building that has been constructed. analyzing a section of the building, barry says that the lowest part of the section must have been constructed the parts above it were constructed. he bases this conclusion on the principle of . also, looking at a crack forming in the building wall, he says that the crack must be the wall. barry used the principle of to arrive at this conclusion.

Which natural occurrence is shown ? check all that apply. 1.drought 2.flooding 3.earthquake 4.long term environmental change 5.short term environmental change

The largest sink for carbon dioxide is in the forests of the earth. a. true b. false