Correct answers are found through links located at the end of each question. Answers for problems will have an additional link to a problem solution screen. If you bring up such a solution screen be sure to close it by clicking the button in the upper left corner or upper right corner. The answer section is formatted for on-screen use, not printing, and will waste a lot of paper if printed directly. A virtual image is the result of your eyes' and brain's interpretations of light rays, not actual light rays originating from an image.
Light rays do originate from a real image, such as the one on a movie screen.
A light ray moving from water to air will be refracted away from the normal. An incident ray that is perpendicular to the surface is not refracted at all. However, the fish will appear larger then it really is since other light rays will be refracted away from the normal. This is a definition of the index of refraction. Waves shorter than microwaves fall in the zone of infrared radiation.