Dolphins of the open ocean are classified as Type II Odontocetes (toothed whales). These animals use ultrasonic “clicks” with a frequency of about 55 kHz to navigate and find prey. (a) Suppose a dolphin sends out a series of clicks that are reflected back from the bottom of the ocean 75m below. How much time elapses before the dolphin hears the echoes of the clicks? (The speed of sound in seawater is approximately 1530m/s). (b) What is the wavelength of 55 kHz sound in the ocean?