The largest breed of rabbit is the White Flemish Giant, which
can have a mass of up to 8 kilograms.
In a report, Rebecca said that the
mass of this kind of rabbit could be
up to 800 grams. Was Rebecca’s report
correct? Explain.

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.