What is the order of magnitude of the number 500

Do 12/14 and 8/10 have the same value? explain your answer.

Ineed someone to me answer my question i have to have this done and knocked out

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?