A bat emits a sound at a frequency of 3. 00 × 104 hz as it approaches a wall. The bat detects beats such that the frequency of the echo is 900 hz higher than the frequency the bat is emitting. The speed of sound in air is 340 m/s. The speed of the bat is closest to.

Which statement best describes gravity? it is the force that repels only very small objects. it is the force that acts between objects with zero mass. it is the force that sometimes acts only on very large objects. it is the force that acts between any two objects in the universe.