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Mathematics>Standard Multiple Choice

Read the following SAT test question and then click on a button to select your answer.

Three electricity plans are available in a certain county. The monthly usage and corresponding charges for that usage for three households, each using a different plan is shown below. Which plan, if any, has the lowest cost per kilowatt-hour (kWh)?

A.Plan A
B.Plan B
C.Plan C
D.The plans all cost the same amount per kilowatt-hour.

答案和解析

答案：A

解析：

Choice A is correct.