Storing in PlayerPref based on timer

Officially first post on here so take it easy on me. I'm using a js to countdown (using 2 minutes). What I need is to store a 3 (for 3 stars) if they get it done in 1:40-1:50. Store a 2 (for 2 stars) if they get done in 1:50 to 2:00. And store a 1 (for 1 star) if they finish after 2:00. I would then use this value after the next level to display how many stars. I would also use this to unlock a secret level if 3 stars were acheived on all 5 levels. Code for Timer:

  var startTime: float;
  var timeRemaining:float;
  function Start(){
    startTime = 120.0;
    guiText.material.color = Color.red;
  }
  function Update () {
    Countdown();
  }
  function Countdown(){
    timeRemaining = startTime - Time.time;
    ShowTime();
    if(timeRemaining < 0)
    {
      timeRemaining = 0;
      TimeIsUp();

      Debug.Log("Time remaining = "+ timeRemaining);
    }
  }
  function ShowTime(){
    var minutes: int;
    var seconds: int;
    var timeString : String;
    minutes = timeRemaining/60;
    seconds = timeRemaining%60;
    timeString = minutes.ToString() +":" + seconds.ToString("D2");
    guiText.text = timeString;
  }
  function TimeIsUp(){
    Debug.Log("Time is up!");
  }

Right now this works and displays "Time is up!" but I'm wanting it to store those values instead. I'm assuming using PlayerPrefs would be the best way. I also would like a way for my box collider to store a true value in PlayerPrefs so that I could use it for my level unlock screen. Any help is appriciated and I can post more code or info about my game if needed. Thanks

Ok, by not having what the game is, I'll go with what I can.

On the condition that the player HAS finished the game/level, run a function (Done), and pass through the timeRemaining.

Ok, by not having what the game is, I'll go with what I can.

On the condition that the player HAS finished the game/level, run a function (Done), and pass through the timeRemaining.

function Done(float time){
    if(time <= 110.0)
    {
      PlayerPrefs.SetFloat("Player Stars", PlayerPrefs.GetFloat("Player Stars")+3);
    }
    else if(time <=  120&& time >= 110)
    {
      PlayerPrefs.SetFloat("Player Stars", PlayerPrefs.GetFloat("Player Stars")+2);
    }
    else if(time > 120)
    {
      PlayerPrefs.SetFloat("Player Stars", PlayerPrefs.GetFloat("Player Stars")+1);
    }
}

If you have any questions, ask... But this should make sense.... Hope it helped!