what kind of image is formed when light rays parallel to the principal axis of a convex lens falls on it

Q. A convex lens of focal length $f$ is cut into two halves as shown. Light rays parallel to the principal axis are incident on one half of the lens ( say $L_1$ ). This will form an image at :

Q. If all rays falling on a convex lens are parallel to the principal axis of the lens, what happens to them after they pass through the lens?

Q. When a beam of white light parallel to the principal axis is refracted through a convex lens, then the rays converge to the principal axis. If a screen is placed at a sufficient distance from the focus-point perpendicular to the principal axis then the image on the screen will be.

Q.

A ray of light falling parallel to the principal axis on a convex mirror follows ray number ___ as its path.

Q. A ray of light, after refraction through a convex lens emerges parallel to the principal axis. The incident ray when produced appear to come from a point on principal axis. Name the point :