What are the uses of ultrasonic sound?

Name the following Technology that uses ultrasonic sound waves to generate images of internal organs of the human body.

A bat flying above lake emits ultrasonic sound of 100 kHz ,When this wave falls on the water surface, it is partly reflected and partly transmitted .The wavelengths of the reflected and the transmitted waves are (The speed of sound in air is 340 m/s and in water is 1450 m/s)

Answer the following Give one example cach of infra sound a ultrasonic sound?

What is the unit of intensity of sound ?

A bat emits ultrasonic sound of frequency 100 kHz. If this sound meets a water surface what is the wavelength of the transmitted sound in air and water respectively?