(1) Assume that the lights in your kitchen use 300 watts. How much energy (in kWh) does it use and how much does it cost to leave the lights on 24 hours a day for one year if electricity is 12cents/kilowatt hour

the cost to leave the lights on 24 hours a day for one year is 31,536 cents or 315.36 dollars

Explanation:

Given that;

P = 300 watts = 300/1000 = 0.3

t = 24hrs a day

In a calendar year, we have 365 days

so;

E = 0.3 × 365 × 24

E = 2628 KWh

given that;  1 KWh = 12 cent

then 2628  KWh is x

x = 2628 × 12

x = 31,536 cents or 315.36 dollars

Therefore, the cost to leave the lights on 24 hours a day for one year is 31,536 cents or 315.36 dollars