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 can hear frequencies from about 20 hertz to 20 kilohertz, dogs from about 20 hertz to 40 kilohertz, and cats from about 30 hertz to 60 kilohertz. âCats are capable of hearing the very high pitch of high-frequency sounds â it would appear three times as high and ones that humans canât detect.umans can hear frequencies from about 20 hertz to 20 kilohertz, dogs from about 20 hertz to 40 kilohertz, and cats from about 30 hertz to 60 kilohertz. âCats are capable of hearing the very high pitch of high-frequency sounds â it would appear three times as high and ones that humans canât detect.