(3) 5-10 decibels Explanation: Hearing range usually describes the range of frequencies that can be heard by an animal or human, though it can also refer to the range of levels. In humans the audible range of frequencies is usually said to be 20 Hz (cycles per second) to 20 kHz (20,000 Hz), although there is considerable variation between individuals, especially at the high frequency end, where a gradual decline with age is considered normal. Specifically, humans have a maximum aural range that begins as low as 12 Hz under ideal laboratory conditions, to 20 kHz in most children and some adults.