Question 1 (10 points) A year is a leap year if it is divisible by 4, unless it is a century year that is not divisible by 400. Write a program that calculates whether a year is a leap year. Question 2: (10 Points) Write well-documented Python functions for: a. b. sphereArea (radius): Returns the surface area of a sphere having a given radius. sphereVolume(radius): Returns the volume of a sphere having a given radius. Question 3: (10 Points) Write well-documented Python functions for: a. sumN(n): Returns the sum of the first n natural numbers b. sumNCubes(n): Returns the sum of the cubes of the first n natural number:s