Sir Fred Hoyle coined the term ‘big bang’ . It is important to note that the Big Bang theory was proposed by Georges Lemaitre but the term was coined by Fred Hoyle.
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