Fill in the blanks with suitable words:
a) Sound is caused by _______
b) A sound wave consists of places of higher pressure called _______ and places of _______ pressure called _______
c) Wave speed in meters per second equals frequency in ______ multiplied by _______ in ________
d) Sound cannot travel through _______
e) The speed of sound in a solid is _______ than the speed of sound in air.
f) When the frequency of the sound is increased, the wavelength ________