Why does `x = x + 1` work if `=` doesn't mean equals — and what does Python do with the old object in memory?
Short drills on what this video just taught. Write the code, run the checks, and reveal the answer only if you are stuck.
A circle has pi = 3.14 and radius = 10, both given below. Compute the circle's
area — pi times the radius squared — and assign it to area. Remember that Python
applies exponentiation before multiplication.