Brainliest!

which of the following is a statistical question?
a.
how many students attend natasha's school?
b.
how many players are on greg's football team?
c.
what are the checking account balances of the shoppers in a grocery store?
d.
what volume of milk is used to make cupcakes according to paula's cookbook?

Saline iv fluid bags cost $64.20 for 24, 1000 ml bags from one supplier. a new supplier sells 500 ml bags for $2 each. the hospital uses about 10,000, 1000 ml bags each month. nurses report that about half of the bags are more than half full when they are discarded. if you are going to use only one supplier, which size bag provides the best deal, and how much will you save each month? compare the cost of the new supplier to the current one.

Ineed in figuring out this problem.

How is working backward similar to solving an equation?