Carpentry is another profession learned through apprenticeship. An apprenticeship is a system of training a new generation of practitioners of a trade or profession with on-the-job training and often some accompanying study (classroom work and reading). Apprenticeship also enables practitioners to gain a license to practice in a regulated profession.
A black light is a source of electromagnetic radiation that emits near-ultraviolet light, usually in the 350-375 nanometer wavelength range. This range is just slightly below the 400nm that human eyes can detect. When this light is reflected off certain materials, it looses energy and its wavelength expands to over 400nm. The reflected light is then visible to human eyes, and the illuminated objects appear to glow.
The K color, or black, is used to completely remove light from the printed picture, which is why the eye perceives the color as black.[1] RGB Color Mode. RGB is the color scheme that is associated with electronic displays, such as CRT, LCD monitors, digital cameras and scanners. It is an additive type of color mode that combines the primary colors, red, green and blue, in various degrees to create a variety of different colors.