My solution

// Setting crown variable to zero before storing correct answers
  var crowns = 0


// Questions code
  var first = prompt("According to ohms law volts x amps = watts, True of False?");
  if(first == "true" || first == "True") {
      alert("Correct!, you've earned one crown!");
      crowns = crowns + 1;
  } else
      alert("Incorrect!");

  var second = prompt("Correct color phases for a 277v 3 phase panel would be Brown, Orange, Yellow. True of False?");
  if(second == "true" || second == "True") {
      alert("Correct!, you've earned one crown!");
      crowns = crowns + 1;
  } else
      alert("Incorrect!");

  var third = prompt("Correct color phases for a 120v 3 phase panel would be Black, Red, Green. True of False?");
  if(third == "false" || third == "False") {
      alert("Correct!, you've earned one crown!");
      crowns = crowns + 1;
  } else
      alert("Incorrect!");

  var fourth = prompt("According to NEC, maximum distance between supports for MC Cable is _FT?");
  if(fourth == "6" || fourth == "six") {
      alert("Correct!, you've earned one crown!");
      crowns = crowns + 1;
  } else
      alert("Incorrect!");

  var fifth = prompt("The maximum number of current carrying conductors allowed in a single raceway before de-rating must be performed is?");
  if(fifth == "3" || fifth == "three") {
      alert("Correct!, you've earned one crown!");
      crowns = crowns + 1;
  } else
      alert("Incorrect!");

// Crown storage and alerts 

  if(crowns == 5) {
    alert("You've answered 5 out of 5 and earned the gold crown!");
  }
    else if(crowns == 4) {
      alert("You've answered 4 of 5 correct and earn a silver crown!");
    }
    else if(crowns == 3) {
      alert("You've answered 3 of 5 correct and earn a silver crown!");
    }
    else if(crowns == 1 || 2) {
      alert("You've answered less than three correct and earn a bronze crown.");
    }
    else if(crowns === 0) {
      alert("You've answered zero correctly and earn a participation award.");
    }