A helicopter flying 2,000 feet above the ground spots an airplane flying above. If the horizontal distance between the helicopter and airplane is 3,335 feet and the angle of elevation is 85°, find the airplane’s altitude. Round to the nearest tenth.

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.