A certain type of ship has two tanks in its engine. Each tank contains a different type of fuel. When the engine turns on, the same amount of energy is transferred out of both fuels as shown in the diagram below. Why did fuel 1 change phase, but fuel 2 stayed the same? Explain what happened to the molecules of both fuels.

An electric power distributor charges residential customers $0.10 per kilowatt-hour (kwh). the company advertises that "green power" is available in 150 kwh blocks for an additional $4 per month. (green power is generated from solar, wind power, and methane sources.) if a certain customer uses an average of 391 kwh per month and commits to one monthly 150 kwh block of green power, what is her annual power bill