Summer work answer key:

To do this, assume all of the 170 billion tons is glucose. Also, assume tons are metric tons. (Note: 180 grams of glucose when burned in a calorimeter gives off 686 Kcal of energy.) 170 ( 109 metric tons/yr ( 1,000 g/kg ( 1,000 kg/metric ton ( 686 kcal/mole ( 170 ( 1015 g/yr of biomass ( 1 mole of glucose/180 g ( 9.4 ( 1014 moles/yr x 686 kcal ... ................
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