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## Homework Statement

An electric air conditioning unit draws 15 amps of direct current from a 134 V direct voltage source, and is used 24 hours a day during 21.1 days in July. How much will the electricity cost for the month if the local electrical rate is

9.9 /kW· hr?

Answer in units of dollars.

(Note: sigfigs do not matter)

## Homework Equations

P = I*[tex]\Delta[/tex]V

## The Attempt at a Solution

This seems like a straight forward question:

P = 15*134 = 2010 W = 2.01 kW

t = 21.1 days * 24 hours = 506.4 hours

P*t = 1017.864 kW*hr

Since units aren't given for 9.9, I tried for both dollars and cents:

1017.864* 9.9 =

**$10076.85**

1017.864*.099 =

**$100.785**

Both answers are wrong. I don't know where I'm making the mistake.

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