Item 11 Find the perimeter of the window to the nearest tenth.

A semi-circular windowpane with radius labeled 20 centimeters.

perimeter: about___ cm

Oliver read for 450 minutes this month his goal was to read for 10% more minutes next month if all of her medicine go how many minutes will you read all during the next two months

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.

Hundred and tens tables to make 430 in five different ways