HELPP!! Part II: A semi-regular tessellation uses more than one regular polygon to completely cover a surface with no overlaps or spaces. Name the polygons used
in each semi-regular tessellation. (4 points; 2 points each)

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.