The electric force between a charged foam cup and a positively charged metal sphere is 2.12 newtons. if the charge on the cup is 2.0 × 10-6 coulombs and the charge on the metal sphere is 2.5 × 10-6 coulombs, what is the distance between the two? (k = 9.0 × 109 newton·meter2/coulombs2) 9.0 × 10-1 meters 6.4 × 10-1 meters 3.8 × 10-1 meters 2.8 × 10-1 meters 1.5 × 10-1 meters

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