Practicing unit testing using Jest. Tests for the following functions:

A capitalize function that takes a string and returns it with the first character capitalized.

A reverseString function that takes a string and returns it reversed.

A calculator object that contains functions for the basic operations: add, subtract, divide, and multiply. Each of these functions should take two numbers and return the correct calculation.

A caesarCipher function that takes a string and returns it with each character “shifted”.

An analyzeArray function that takes an array of numbers and returns an object with the following properties: average, min, max, and length.