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D Question 15 2 pts A vibrating object produces periodic waves with a wavelength of 87 cm and a frequency of 25 Hz. How fast do these waves move away from the object? Provide the final answer in m/s. D Question 14 2 pts Determine the distance traveled in km, as sound travels through a steel rail in 8.83 s. The speed of sound in steel rail is 5940 m/s. A sound wave in a steel rail of a railroad track has a frequency of 650 Hz and a wavelength of 6.2 m. What is the speed of sound (in m/s) in this rail? D Question 12 2 pts A sonar signal is sent from an oceangoing ship and the signal returns from the bottom 2.3 s later. How deep (in m) is the ocean beneath the ship if the speed of sound in seawater is 1503 m/s? Question 11 4 PLS An echo is heard from a building 0.368 s after you shout "hello." How many feet away is the building if the air temperature is 23.5.C? D Question 9 The upper limit of hearing for a particular human being is 22400 Hz. What is the corresponding wavelength (in m) if the air temperature is 21C? Round answer to 4 decimal places