The angle of depression of a point P on the ground from the top T of a building is 23.6. If the distance from P to the foot of the building is 5 cm. Calculate the height of the building, correct to the nearest degree. ​

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.