Assessment Choose the letter of the correct answer. Write your answers on a separate sheet of paper. B. gas 1. What makes a sound? A. force C. vibration B. instrument D. volume 2. This is a medium where sound travels slowly. A. air C. liquid D. solid 3. In each of our ears, we have a very sensitive membrane called the which also vibrates because of air. A. auricle C. ear canal B. cochlea D. eardrum 4. It is an example of a transducer, a device that changes information from one form to another. A. cellphone C. microphone B. laptop D. speaker 5. It is an echo-sounding device or a technique that uses sound propagation to detect objects on or under the surface of the water. A. Sound Navigator and Range B. Sound Navigation and Range C. Sound Navigator and Ranging D. Sound Navigation and Ranging 6. Where does sound travel fastest? A. air C. metal B. empty space D. water 7. Which of the following materials absorbs most of the energy of sound waves? A. sound conductor B. sound diffuser C. sound generator D. sound insulator​