2) Lens Problems A) A colorful lamp is 80 cm from a screen. You use a lens with a focal length of 20 cm to make a focused image of the lamp on the screen. What are the two possible positions of the lens? B) A photographer uses his camera, whose lens has a 50 mm focal length, to focus on an object 2.0 m away. He then wants to take a picture of an object that is 40 cm away. How far, and in which direction, must the lens move to focus on this second object? C) A nearsighted person wants to see a tree that is 3 meters away from them. Their far point is 1.7m. What is the optical power of the contact lenses that would they need to see the bottle clearly