Infrasound can be heard by

Draw a labelled diagram of the auditory parts of the human ear and explain how the human ear works.

If the amplitude of a wave is doubled, what will be the effect on its loudness?

Flash of lightning reaches earlier than the sound of thunder. Why?

Which of the above two graphs $(a)$ and $(b)$ representing the human voice is likely to be the male voice? Give reason for your answer.

State whether the following statement is true or false:
Sound travels faster at a higher temperature than at a lower temperature.