The outdoor furniture center buys wooden benches for $50 each. the furniture store owner adds a %200 markup to the cost of the bench. after hearing from customers that the selling cost of the bench is too high, the owner changes the markup to 120%. how much less per bench does the store owner make with the lower markup?

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.