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.
Dispersed Settlements − In these kind of settlements, houses are spaced far apart and often interspersed with fields. However, the market and some other activities in these settlements are centralized where they participate together.
The amount of insolation received varies from latitude to latitude. The Regions within the equator and 40° N and S latitudes are energy surplus regions because they receive abundant sunlight and hence more heat will be gained than lost.The Regions beyond 40° N and S latitudes are energy deficit regions because they lose more heat than that gained from sunlight.
EXAMIANS