A 20-oz bottle of soda is $1.79. A 32-oz bottle is $3.49. Which has the lower unit cost? a) the smaller size
b) the larger size
c) the unit cost is the same

Easy, to find the unit cost, divide the price with the ounces.
For the 20-oz bottle of soda that is $1.79, divide 1.79 by 20 oz.
20/1.79= $11.17

For the 32-oz bottle, do the same.
32/3.49 = $9.17

The unit price of the 20-oz bottle would be $11.17, meanwhile the 32- oz bottle would have a unit price of $9.17.

The soda with the lower unit cost would be the larger sized bottle.