A 5 kg mass on a spring is stretched 10 cm and then let go. It oscillates back and forth with a period of 0.7 s. What is the spring constant k

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