Use the model to solve for x

Which of these tables represents a non-linear function?

The volume of a sphere is increased by 6%. calculate the corresponding percentage increased in it area.

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?