How Much Money Would You Save Per Hour by Replacing

Multiple Choice

How much money would you save per hour by replacing a 100-watt incandescent light bulb with an equally bright 20-watt fluorescent bulb? Assume the cost for electricity to be 15 cents per kilowatt-hour.

A) 1.5 cents per hour
B) 1.2 cents per hour
C) 0.3 cent per hour
D) It's not possible to save only a fraction of a cent.