How do a neutron and a proton compare? a. there are more protons than neutrons in an isotope. b. they have about the same mass. c. the proton has a positive charge, while the neutron has a negative charge. d. the neutron is farther from the nucleus.

Which statement best describes the superposition principle? a.) if two in-phase waves arrive simultaneously at a point, their amplitudes add up b.) if two out-of-phase waves arrive simultaneously at a point, their amplitudes add up c.) if two in-phase waves arrive at a point one after another, their amplitudes add up d.) if two out-of-phase waves arrive at a point one after another, their amplitudes adds up