Answer:
The answer is B on khan academy
Explanation:
Answer:
For the bird moving in a straight line, the kinetic energy is one-half the product of the mass and the square of the speed: Ek=12mu2.
The answer is a because it never needs to be insulated
Explanation:
For example, when a drum is struck, the flexible skin (sometimes called a membrane) of the drum vibrates. The compression and expansion of the air on either side of the vibrating membrane produces differences in air pressure. The pressure differences generate a sound wave that propagates outward from the drum surface.
