Answer: A different group of scientists using different methods.
Explanation:
The relation between
is given by :

Where :
= Ionic prodcut of water
The value of the first ionization constant of sodium sulfite = 
The value of
:


The value of the second ionization constant of sodium sulfite = 
The value of
:


Answer:
5=C, every action has an equal or opposite reaction,
6=B, since it has less air drag and more force exerted on it
7= You're correct