Maria created this graphic organizer to classify different figures. The left circle represents isosceles triangles. The right circle represents obtuse triangles. Which figure belongs in the part of the organizer where the circles overlap?

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?