Since the demand for woollen garments is confined only to the colder parts of the globe, woollen textile industry ismuch smaller and less widely distributed than the cotton textile industry. Two-thirds of the world’s woollen mill capacity and production are located in Europe.
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.
EXAMIANS