The resolving power of a telescope depends on which one of the following factors?

The aperture of the objective of a telescope is $0.1$metre and the wavelength of light is $6000 \text{Å}$. Resolving limit will be nearly:

How the resolving power changes when the space between the object and the objective of a microscope is filled with water?

What should be the position of an object relative to a biconvex lens so that it behaves like a magnifying glass?

What is the angular magnification produced by a single convex lens used as a simple microscope in ‘normal’ use?

An object is seen first in red light and then in violet light through a simple microscope. In which case will the magnifying power be larger?