You can remember the three numbers to your combination lock, but you can't remember their order. How many
different combinations of the three numbers will you have to try, at most

Answer this question only if you know the answer! 30 points and

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.

Which expression and diagram represent “renee biked four times as far this month as last month”?