Unkown Identifier: 'Math'.

Im trying to get a random GameObject to spawn based off of what value is pulled from my array. But Untiy is returning the error "Assets/SpawnScript.js(27,39): BCE0005: Unknown identifier: 'Math'." This is my code:

var powerUp = ['FireSpeed','Movement','SlowTime'];

function PowerUp()
{

 var rand = powerUp[Math.floor(Math.random() * powerUp.length)];  

 if (rand === 'FireSpeed') 
 
 {  
     Instantiate(fireSpeed, transform.position, transform.rotation);  
     GetComponent.<Rigidbody2D>().AddForce(transform.up);  
 }  

 if  (rand === 'Movement')  
 {  
     Instantiate(movement, transform.position, transform.rotation);  
     GetComponent.<Rigidbody2D>().AddForce(transform.up);
 }
 if (rand === 'SlowTime')
 {
     Instantiate(slowTime, transform.position, transform.rotation);
     GetComponent.<Rigidbody2D>().AddForce(transform.up);        
 }

}