text: //Basic Function Syntax
  function alertRandom() {
      var randomNumber = Math.floor( Math.random() * 6 + 1);
      alert(randomNumber);
  }
  
  /*
  alertRandom();
  alertRandom();
  alertRandom();
  alertRandom();
  alertRandom();
  alertRandom();
  */
  
  
  //Function expression syntax (assigned to variable)
  var alertRandom2 = function () {
      var randomNumber = Math.floor( Math.random() * 6 + 1);
      //alert(randomNumber);
  };
  
  alertRandom2();
  
  //Return from function
  function alertRandom3( lower, upper ) {
      if (lower >= upper) {
          return "Please enter the lower number first."
      } else if ( isNaN(lower) || isNaN(upper)){
          throw new Error("Enter a valid number, you idiot.")
          } else {
          return Math.floor(Math.random() * (upper - lower) + lower);
      }
  }
  
  alert( alertRandom3( 'fifteen', 20 ) );
  
  alert( alertRandom3( 200, 100 ) );
  
  
  //Calculate area
  function getArea( length, width, unit){
      var area = length * width;
      return area + ' '+ unit;
  }
  
  //alert(getArea( 3, 4, 'sq ft'));
  