Rising saturated air cools at a lesser rate than rising unsaturated air primarily because: a. rising saturated air is heavier b. latent heat of condensation is released in a rising parcel of saturated air c. rising saturated air is lighter d. unsaturated air expands more rapidly e. saturated air does not expand

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