How does a convex lens produce real image from virtual object?

In the shown situation, if middle portion of the lens is painted black, then

Four bulbs; red, green, white and blue (denoted by $R, G, W$ and $B$ respectively) are kept in front of a converging lens (as shown in the figure below). The observer sees that the green and blue bulbs are kept to the left of the principle axis while the red and white bulbs are kept to the right of the principle axis. He also sees that the red and green bulbs are above the principle axis while the white and blue bulbs are below the principle axis. The screens $S_1$ and $S_2$ are set at appropriate positions for the focusing to view the images.

Choose the figure that correctly represents the images as seen by the observer.

When a drop of water is introduced between the glass plate and plano convex lens in Newton's rings system, the ring system:

In between a fixed object and a fixed screen a convex lens can cast two images at two different positions of the lens. Taking this to be a true statement show that the product of the size of the images is equal to the square of the object size.

A converging mirror is placed on the right hand side of a converging lens as shown in the figure. The focal length of the mirror and the lens are $20 \mathrm{cm}$ and $15 \mathrm{cm}$ respectively. The separation between the lens and the mirror is $40 \mathrm{cm}$ and their principal axes coincide. A point source is placed on the principal axis at a distance $d$ to the left of the lens. If the final beam comes out parallel to the principal axis, then the value of $d$ is:

The word KVPY is written on $\mathrm{a}$ board and viewed through different lenses such that board is at a distance beyond the focal length of the lens.

Ignoring magnification effects, consider the following statements.
$\left(\mathrm{I}\right)$ First image has been viewed from the planar side of a plano-concave lens and second image from the planar side of a plano-convex lens.
$\left(\mathrm{II}\right)$ First image has been viewed from the concave side of a plano-concave lens and second image from the convex side of a plano-convex lens.
$\left(\mathrm{III}\right)$ First image has been viewed from the concave side of a plano-concave lens and second image from the planar side of a plano-convex lens.
$\left(\mathrm{IV}\right)$ First image has been viewed from the planar side of a plano-concave lens and second image from the convex side of a plano-convexlens.

Which of the above statements are correct?