When a convex lens produces a real image of an object, the minimum distance between the object and image is equal to

Where should an object be placed in front of a convex lens to get a real and enlarged image of the object ?

A convex lens has a focal length of 15 cm. At what distance should an object be placed in front of the lens to get a real image of the same size of the object?

An object is placed between infinity and the pole (P) of a convex mirror. The position of the image is

What is the magnification produced by a concave lens of focal length 10 cm, when an image is formed at a distance of 5 cm from the lens?

What will be the nature of image formed by a convex mirror when the position of object is between infinity and pole P of the mirror?