1. The problem statement, all variables and given/known data 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) 2. Relevant equations P = I*[tex]\Delta[/tex]V 3. 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.