Which of the two produces ultrasonic waves: porpoise or whale?

Define the following terms:

(1) Echolocation

(2) Echocardiography, and

(3) Ultrasonography.

Name an animal which navigates and find food by echolocation.

What is sonar? Explain its use.

A sonar station picks up a return signal after 3 seconds. How far away is the object? (Speed of sound in water = 1440 m/s).