A large appliance such as a water heater is only running when it has clicked on and is actually heating water. The time your water heater is on varies according to how much you do laundry, take showers, or run the dishwasher. The national average is 3 hours per day.
a. If a water heater uses 4,200 watts, find the daily cost of running it at a cost of $0.11 per kilowatt-hour. Round to the nearest ten cents.
b. Find the annual cost of running the water heater to the nearest ten dollars.
c. A certain energy-saving water heater sells for $1,100. It will save 36% in energy costs per year compared to the water heater from parts a and b. What will be the approximate annual cost of running this water heater? Round to the nearest ten dollars.d. In how many years will the new water heater "pay for itself"?