C should be it. Correct me if im wrong xd
Number one a and b are automatically out if you decrease the pitch or frequency you wont hear it louder it does not add up ok?
number 2 the answer would be C the higher the frequency the higher the pitch the lower the frequency the lower the pitch this just comes back to common sense. for example you cant decrease the frequency and than expect a louder pitch its like saying I am going to smash the key on this piano with all my strength and it will make a small very low pitch sound you get what I mean so your answer would indeed be C.
Answer:
The process by which wind removes surface materials is called deflation.
Answer:
k is the energy of motion it increase with four of load you carry
