Two thin lenses of power +4 D and -2 D are in contact. What is

power 4dThe power to move, walk and travel in four dimensions. Sub-power of Unrestricted Movement and 4th-Dimensional Access. Technique of Space-Time Manipulation and Dimension Manipulation.Answer:the power of a convex lens is always positive. as you can see here the power is +4D, therefore the nature of the lens is that it is a convex lens. we know, P = 1f. also