Acylindrical candle has a radius 1.5 in and a height of 4 in what is the volume of the candle in cubic inches in cubic centimeter use pia and round your answer to the nearest hundred

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.