The independent variable is is the price per bag.
The answer is C) because one litre=100 centiliters, and one kilolitre=one litre which means that one kilolitre =100000 centiliters
So 140 centiliters are 140 divided by 100000 kiloliters=0.00140 kiloliters
7 is just adding.
8 is counting by odd numbers.
9 is a rotation