Question

SI unit of velocity of sound

Answer 1

SI unit of sound is decibel (dB)
Human can hear a minimum of 20 dB of sound and a maximum of 20000bB

Answer 2

Sound can be described as a wave in which case it has wavelength (lambda expressed in the SI unit meter), frequency (Hertz equal to cycles per second, which is a rate but directly based on the SI unit 'second') and velocity (m/s, although this velocity could mean both horizontal velocity of a pattern in the wave