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.
The average frequency range for human speech varies from 80 to 260 Hertz. The vocal speech frequency of an adult male ranges from 85 to 180 Hertz, while the frequency of an adult female ranges from 165 to 255 Hertz. Keep Learning.