Which part of the diagram indicates the amplitude of the wave?

Answer : The rest position to the crest indicates the amplitude of the wave.

Explanation :

Amplitude of the wave : It is a wave that covers maximum amount of displacement on the medium from its rest position.

That means, the amplitude can be measured from rest position to the crest and also measured from rest position to trough.

Wavelength of the wave : It is the length of one complete wave cycle.

That means, the wavelength can be measured from crest to crest and trough to trough.

Hence, the rest position to the crest indicates the amplitude of the wave.

c)as speed changes, wavelength and frequency change.

everything changes!

answer: 802.3 kilo joules of energy represents 191.75 kilo calorie of energy.

explanation:

energy released during combustion of one mole methane = 802.3 kilo joules

if 1 kilo joule = 0.239006   kilo calorie

then ,802.3 kilo joule will be = 802.30.239006 kilo calorie

802.3 kilo joule = 191.75 kilo calorie

hence, the energy in kilo calorie is 191.75 kilo calorie.