Mohan obtained a sharp inverted image of a distant tree on the screen placed behind the lens. He then moved the screen and tried to look through the lens in the direction of the object. He would see: (1) a blurred image on the wall of the laboratory. (2) an erect image of the tree on the lens. (3) no image as the screen has been removed (4) an inverted image of the tree at the focus of the lens.