Two manufacturing plants need 1.0e4 kg of Al each week. One plant produces the Al from bauxite (Al2O3), whereas the other gets its Al from recycled cans. Given that recovery of recycled Al consumes only 5% of the energy it takes to manufacture Al from bauxite, what is the dollar difference in energy costs for the two plants? For this problem you should only consider the Al energy costs. Assume each company pays $0.04 per kwhr and the ?Hf for Al2O3 is -1676 kj/mole. Finally, you will need this conversion factor: 1 watt-hr = 3600 joules.
A. $163,928.
B. $6902.
C. $6557.
D. $3451.
E. $3279.