Instantiate Random Object at Random Position

//Thoose are objects that i have;

        var shooterPlatform : GameObject;
        var wireFrame : GameObject;
        var passObj : GameObject;
        var bareels : GameObject;
     
        //This is array List;
        var randomObject;
         
        //This is the variable of Randomly selected object;  - not required
        // var randomSelect;
         
             
           
            function Awake()
            {
                //--------------------------------------------------------------------------
                 
                //At there, Instantiate the object that selected randomly
         
                randomObject = new Array(shooterPlatform, wireFrame, passObj, bareels);
         
            }
           
            function Update () {
               
                var randomSelect = Random.Range(0,(randomObject.length)); //since you want to get a random object every time
     
                var position = transform.TransformPoint(Random.Range(-3.704676, 5.132769), 0, Random.Range(-3.704676, 5.132769));
               
                //At there, Instantiate the object that selected randomly :S But it isn't worked
               
                Instantiate(randomObject[randomSelect], position, Quaternion.identity);
               
            }

I wrote this code for random object creation but it says “var randomSelect = Random.Range(0,(randomObject.length)); //since you want to get a random object every time”

I think there is en error Log says me : "lenght’ is not a member of ‘Object’. "

I’m really confused now.

// in the declaration
var randomObject : Array;

Edit : For more information, take a look at the section #2 of Performance Optimization.