(1) An object of size 7 cm is placed at 25 cm in front of concave mirror of focal length 15 cm. At what distance from the mirror should a screen be placed, so that we can get a sharp and clear image. Find nature and size of the image.
(2) An object of height 5 cm is held 20 cm away from converging lens of focal length 10 cm. Find the position, nature and size of the image formed.
(3) An object is placed at a distance of 10 cm from a convex lens of focal length 12 cm. Find the position and nature of the image.