(a)[3]
Calculate how far the fish is from the boat.
(b)[1]
Tick the box next to the correct statement about ultrasound. The frequency of ultrasound is below 20 Hz. The frequency of ultrasound lies between 20 Hz and 2000 Hz. The frequency of ultrasound lies between 2000 Hz and 20000 Hz. The frequency of ultrasound is above 20000 Hz.
(c)[1]
State the name of one wave in the electromagnetic spectrum.