Let's tackle subtraction first. Subtraction in hexadecimal works similar to subtraction in decimal. Let's do a pair of decimal problems and see if we can parallel the solution method in hex. Suppose we want to subtract 1586 - 243 (in decimal).
Refraction of Light Rays. the bending or deflection of light rays as they pass through the various media of the eye that include the conjuctiva, cornea, aqueous humor, lens, and vitreous body.
However, if it occurs frequently, you should have your eyes examined just in case it is a sign of something serious. Seeing stars is a common visual complaint, but it is usually a normal and harmless occurrence. If you close your eyes and rub them, you will probably see spots and flashes of light. These images you see are called phosphenes, an entoptic phenomenon characterized by the experience of seeing light without having light actually enter the eye. Phosphenes are produced by pressure on the eye.