The picture shows a triangular island: Which expression shows the value of q?
A. r cos 550
B. r sin 550
C. sin over 55°
D. cos over 55°

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.