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1:52 PM Bull, , , , S|, , , , , , < Hh ? :, , Audible and Inaudible sounds, , Sound of frequency range between 20Hz to, , 20,000 Hz are called audible sound ., , Sound of.frequency below 20Hz and above, , 20,000 Hz is called sound of n audible range.., , Sound having frequency higher than, , 20,000Hertz are known as ultrasonic sounds., , Some animals like bats,dogs, dolphins can, , hear ultrasonic sounds.., , Sounds having frequency lower than 20, , Hz are known as infrasonic sounds.., , Earthquake waterfall, volcanic eruption are, , example of infrasonic sound..