Hi im getting this error in my script Assets/MouseManager.cs(11,27): error CS1525: Unexpected symbol `Vector3'

using UnityEngine;
using System.Collections;

public class MouseManager : MonoBehaviour {

void Update() {
	if( Input.GetMouseButtonDown (0)
	    // We clicked, but on what?

    
	    Vector3 mouseWorldPos3D = Camera.main.ScreenToWorldPoint(Input.mousePosition);

	    Vector2 mousePos2D = new Vector2(Input.mouseWorldPos3D.x, Input.mouseWorldPos3D.y);
	
	    Vector2 dir = Vector2.zero;

	    RaycastHit2D hit = Physics2D.Raycast (mousePos2D, dir);
	    if(hit != null && hit.collider!=null) {
	       // We clicked on SOMETHING that has a collider
	       if(hit.collider.rigidbody2D !=null) {
	           hit.collider.rigidbody2D.gravityScale = 1;
		  }
	  }
  }

}

You need brackets over:

 Vector3 mouseWorldPos3D = Camera.main.ScreenToWorldPoint(Input.mousePosition);
         Vector2 mousePos2D = new Vector2(Input.mouseWorldPos3D.x, Input.mouseWorldPos3D.y);

Like this:

{

}