Figure shows a container of width $H.$ A telescope is fitted at a height $H$ above the base on its side wall such that it is focussed at the point $A$ as shown. Now aliquid is poured slowly in the container. The refractive index of liquid is $\mu =\sqrt{2}.$ Select the correctalternatives

When the space between two glass lenses in combination shown in figure is filled with water, then

. A point object is placed $30 \mathrm{cm}$ in front of an equiconvex lens of radius of curvature $15 \mathrm{cm}$ and made of glass of refractive index $\frac{3}{2}.$ On placing a convex mirror of radius of curvature $15 \mathrm{cm}$ behind the lens on image side as shown in figure, the final image is found to coincide with the object. The possible distance $\mathrm{x}$ between convex lens and convex mirror is

A converging lens is used to form an image on a screen. When the upper half of the lens is covered by an opaque screen