Alaska has a land area about 1,700,000 km² florida has a land area 1/10 of the size of alaska what is the land area florida explain how you found your answer

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?