Which division problem does the number line below best illustrate? A number line going from 0 to 2 in increments of 0.2.

2 divided by one-fifth = 10
1 divided by one-fifth = 10
2 divided by one-tenth = 5
1 divided by one-tenth = 5

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.