The cone shown has a radius of 5 inches and a slant height of 8 inches. Rounded to the nearest whole number, what is the total surface area? Use 3.14 to approximate pi

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?