(a(i))[1]
To make the sound louder, increase the [BLANK] of the sound wave.
(a(ii))[1]
To make the sound pitch higher, increase the [BLANK] of the sound wave.
(b(i))[1]
State the total distance travelled by the sound in the $0.56\,\text{s}$.
(b(ii))[3]
Calculate the speed of sound in air from the measurements given in part (b).
(b(iii))[2]
Suggest two ways to improve the students’ experiment.