PLEASE HELP The Greenland Ice sheet contains about 3 million cubic kilometers of ice. If completely metled, this ice would release about 2.7 million cubic kilometers of water, which would spread out over Earth's approximate 339 million square kilometers of ocean surface. How much would the sea level rise?

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?