alleryStart learning →A 100 W lamp becomes 20 W, used 5 h/day for 30 days. Energy saved?
A3 kWh
B12 kWh
C15 kWh
D9 kWh
Answer & Solution
Correct answer: B. 12 kWh
The 80 W reduction over 150 hours saves 12000 Wh, or 12 kWh.
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