Origins of the Domino Theory. In September 1945, the Vietnamese nationalist leader Ho Chi Minh proclaimed Vietnamâs independence from France, beginning a war that pitted Hoâs communist-led Viet Minh regime in Hanoi (North Vietnam) against a French-backed regime in Saigon (South Vietnam).
The human range is commonly given as 20 to 20,000 Hz, though there is considerable variation between individuals, especially at high frequencies, and a gradual loss of sensitivity to higher frequencies with age is considered normal.
Humans hear frequencies from 20 Hz up to 20,000 Hz. The lowest bound, 20 Hz, with a wavelength of nearly 20 meters, is a frequency we feel rather than actually hear.This test helps you benchmark the lowest limit of your audio system's frequency extension.umans hear frequencies from 20 Hz up to 20,000 Hz. The lowest bound, 20 Hz, with a wavelength of nearly 20 meters, is a frequency we feel rather than actually hear.