Imagine a 40,000-km steel pipe that forms a ring to fit snugly entirely around the circumference of earth. suppose that people along its length breathe on it so as to raise its temperature by 1°c. the pipe gets longer—and is also no longer snug. how high does it stand above ground level? show that the answer is an astounding 70 m higher! (to simplify, consider only the expansion of its radial distance from the center of earth, and apply the geometry formula that relates circumference c and radius r:  c=2πr.)