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.
It is common for people to experience slight hearing loss as the age. This is caused by changes in the inner ear. An average middle-aged person can detect a maximum frequency of 12,000 Hz to 15,000Hz. Some animals have wider frequency ranges. For instance, dogs have an average frequency range of 67 to 45,000 Hz, and dolphins have a maximum frequency range of up to 100,000 Hz. Learn more about Human Anatomy