Can you guys please answer this question I had problem answering in Traveling waves and sound chapter

16: Traveling Waves and Sound m Multiple-Choice Questions 13. 0 0 An AM radio listener is located 5.0 km from the radio antenna. If he is listening to the radio at the frequency of 660 kHz, how many wavelengths t in the distance from the antenna to his house? A. 11 B. 22 C. 33 D. 132 14. BIO 0 0 The probe used in a medical ultrasound examination emits sound waves in air that have a wavelength of 0.12 mm. What is the wavelength of the sound waves in the patient? A. 0.027 mm B. 0.12 mm C. 0.26 mm D. 0.54 mm 15. BIO 0 Ultrasound can be used to deliver energy to tissues for therapy. It can penetrate tissue to a depth approximately 200 times its wavelength. What is the approximate depth of penetration of ultrasound at a frequency of 5.0 MHz? A. 0.29 mm B. 1.4 cm C. 6.2 cm D. 17 cm EU 16. 0 A sinusoidal wave traveling on a string has a period of 0.20 s, a wavelength of 32 cm, and an amplitude of 3 cm. The speed of this wave is A. 0.60 cm/s. B. 6.4 cm/s. C. 15 cm/s. D. 160 cm/s. 17. - 0 A scientist measures the speed of sound in a monatomic gas to be 449 m / s at 20C. What is the gas? A. Hydrogen B. Helium C. Neon D. Argon 18. - 0 Two strings of different linear density are joined together and pulled taut. A sinusoidal wave on these strings is traveling to the right, as shown in Figure (216.18g. When the wave goes across the boundary from string 1 to string 2, the frequency is unchanged. What happens to the velocity? A. The velocity increases. B. The velocity stays the same. C. The velocity decreases. 18. 0 0 Two strings of different linear density are joined together and pulled taut. A sinusoidal wave on these strings is traveling to the right, as shown in Figure Q16.18|E'. When the wave goes across the boundary from string 1 to string 2, the frequency is unchanged. What happens to the velocity? A. The velocity increases. B. The velocity stays the same. C. The velocity decreases. Figure Q16.18 19. 0 0 You stand at x = 0 m, listening to a sound that is emitted at frequency f3. Figure Q16.19|L:' shows the frequency you hear during a four-second interval. Which of the following describes the motion of the sound source? A. It moves from left to right and passes you at t = 2 s. B. It moves from right to left and passes you at t = 2 s. C. It moves toward you but doesn't reach you. It then reverses direction at t = 2 s. D. It moves away from you until I = 2 s. It then reverses direction and moves toward you but doesn't reach you