2.6 x 10^2 / 365 = 0.7123 lb of oxygen each day per tree
0.7123 x 3.9 x 10^11 = 2.8 x 10^11 lb produced in the rain forest each day
answer
2.8 x 10^11
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0.000000783 = 7.83 x 10^-7 scientific notation
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(19.2 x 10^8) / 60 = 0.32 x 10^6 = 3.200 x 10^7
answer: B. 3.200 x 10^7
