Please solve the area for the 3 objects! I giving a lot of points for it and its only area.

You are standing next to a really big circular lake. you want to measure the diameter of the lake, but you don't want to have to swim across with a measuring tape! you decide to walk around the perimeter of the lake and measure its circumference, and find that it's 400\pi\text{ m}400? m. what is the diameter dd of the lake?

Find the interior angle of a regular polygon which has 6 sides

The graph shows how many words per minute two students read. drag to the table the unit rate that matches each graph.