text: def add(a, b):
      print(f"ADDING {a} + {b}")
      return a + b
  
  def subtract(a, b):
      print(f"SUBTRACTING {a} - {b}")
      return a - b
  
  def multiply(a, b):
      print(f"MULTIPLYING {a} * {b}")
      return a * b
  
  def divide(a, b):
      print(f"DIVIDING {a} / {b}")
      return a / b
  
  print("Let's do some math with just functions!")
  
  age = add(30, 5)
  height = subtract(78, 4)
  weight = multiply(90, 2)
  iq = divide(100, 2)
  
  print(f"Age: {age}, Height: {height}, Weight: {weight}, IQ: {iq}")
  
  # A puzzle for the extra credit, type it in anyway.
  print("Here is a puzzle.")
  
  what = add(age, subtract(height, multiply(weight, divide(iq, 2))))
  print("That becomes: ", what, "Can you do it by hand?")
  