Answer:
(2x + 4)(x - 4)=2x^2-4x-16
Answer is (c), the latent heat of fusion. That is by definition the heat that 1 kg of a substance must absorb to melt in the vicinity of its melting point.
Sound waves require a medium. For example - think about space. there is no air or liquid because it is a vacuum, which is why sounds don’t travel through space.
Gravity is a force because it pulls down on objects.
