Astudent ties down one end of a length of rope, then moves the other end back and forth rapidly. the wave that results in the rope is an example of a a. electromagnetic wave b. longitudinal wave c. transverse wave d. mechanical wave of zero amplitude

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