What does each small square in the model represent?

Ineed with this. the figure is made up of a square and a rectangle. find the area of the shaded region.

Determine whether the set of whole numbers is closed under addition. explain why the set is or is not closed. give an example.

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