Chapter P, Problem 17E

The Size of the Earth The radius of the Earth is approximately $4000$ miles.

a. How far is it around the equator? (Hint: You are looking for the circumference of a circle)

b. What is the volume of the Earth? (Hint: The volume of a sphere of radius $r$ is given by $\frac{4}{3}\pi r^3$.)

b. What is the surface area of the Earth? (Hint: The surface area of a sphere of radius $r$ is given by $4\pi r^2$.)