ページの作成:「Normally we humans can hear sound intensity from 20 to 20,000 hertz. A sound that is beyond or below such range fades of our range of hearing. Happen to be some animals l…」
(ページの作成:「Normally we humans can hear sound intensity from 20 to 20,000 hertz. A sound that is beyond or below such range fades of our range of hearing. Happen to be some animals l…」)