Find the range of this equation

Which statement about the annual percentage rate (apr) is not true?

Answer pls man im trying to get out of summer school

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?