The hallways of a three-story building in Denver, Colorado, use 600 lights per floor, and each light is an incandescent bulb rated at \(60 \mathrm{~W}\).

a. Estimate the amount of energy that could be saved in August by turning the lights on when the sun sets and turning them off when it becomes light.

b. Assuming that the power for the lights comes from a \(30 \%\) efficient coal-fired power plant, estimate the amount of \(\mathrm{CO}_{2}\) that would be saved with this conservation measure. Assume that the chemical composition of the coal is \(\mathrm{CH}_{0.8}\) and that coal has a heating value of \(29 \mathrm{MJ} / \mathrm{kg}\).

c. Prepare a brief report, making recommendations for reasonable conservation measures.