Astraw for a box drink is 4 1/8 inches long and costs 0.015 to make. the straws are laid end to end in a line until they extend 123 3/4 inches. how many straws are in the line and how much do they cost ?

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.