Why do solids have a definite shape and volume.?

Holes drilled several kilometers into earth’s crust provide direct evidence about earth’s interior in the form of

Which composition of water moves to begin a deepwater current?

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