There are 4 tiers of seats in each section. each tier is 4 times greater than the tier below. the first tier contains 4 seats. how many seats are in the second tier?

You just told us that "Each tier is 4 times greater than the tier below."
So if the first tier has 4 seats, then the second one has (4x 4) = 16 seats.

We didn't even need to know that there are 4 tiers of seats in the section.

A much more interesting question would be:

                   How many seats are there in the whole section ?

128/3reason being 5 and 1/3 = 16/316/3 • 2/3 = 32/31 and 1/3 = 4/3 32/3 • 4/3 this will equal 128/3