8. Expo markers cost $4.99 per pack. There is a 20% discount if 4 or more packs are purchased at Office
Depot. Sales tax is 7%. If Nicole bought 8 packs of
expos, about how much did she pay?

Set $r$ is a set of rectangles such that (1) only the grid points shown here are used as vertices, (2) all sides are vertical or horizontal and (3) no two rectangles in the set are congruent. if $r$ contains the maximum possible number of rectangles given these conditions, what fraction of the rectangles in set $r$ are squares? express your answer as a common fraction.