Ultrasound refers to a sound wave with a frequency greater than the upper limit of human hearing, which is generally over 20 kHz. In general, humans can hear sounds with a frequency between 20 Hz and 20 kHz.
Etchplain is a plain where the bedrock has been subject to considerable subsurface weathering is called an Etchplain. The process of the formation of Etchplains is called Etchplantation.Flared slope is a rock-wall with a smooth transition into a concavity at the foot zone is called a Flared zone. They are found in a variety of climates. They are most common in granitic rocks.
The South China Sea is a marginal sea of the Western Pacific Ocean. It is the biggest sea by size. It is bounded in the north by the shores of South China, in the west by the Indochinese Peninsula, in the east by the islands of Taiwan.
EXAMIANS