Operating system that has features similar to desktop operating system but is simpler and significantly smaller

All of the following are characteristics that must be contained in any knowledge representation scheme except

In my email i got a message it says a quick message and in message details on who its from its says nicole and under nicole is 50e0bf08e5b671@ualwgypg91wa5wl. uzo9kbud3qjwddygd5.vng -

Why were most movies from the late 1890s until the early 1930s only filmed in black and white? there were only a few people who could afford the technology to produce color motion pictures back then. audiences did not want color motion pictures until later. the film used to make color motion pictures often overheated, which was a safety hazard, so it was generally not allowed. color films had to be hand-colored, frame by frame.