Two football players are attempting to tackle each other. If one football player has a mass of 100 kg and pushes with a force of 100N onto another football player whose mass is 80kg, how much force does the other player push back with?

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