Please please help ASAP Choose the letter if the best answer

2. The Doppler effect caused an apparent

A. loudness

B. Intensity

C. Pitch

D. resonance

3. Beats result from

A. reflection

B. Refraction

C. Diffraction

D. Interference

4. The hammer, anvil, and stirrup are in the

A. outer ear

B. Middle ear

C. Inner ear

D. Cochlea

5. Sonar is used to find

A. time

B. speed

C. angle of reflection

D distance