For the majority of people, Social Security Disability benefits are not taxable. This is true for people who have income in addition to disability benefits as well as those who do not. (Most of the one-third of disability recipients who do pay taxes on benefits receive SSDI benefits, not SSI.
Mixing all three gives black. The CMYK color model (process color, four color) is a subtractive color model, used in color printing, and is also used to describe the printing process itself. CMYK refers to the four inks used in some color printing: cyan, magenta, yellow, and key (black).
Red, Green, Blue-Additive colors. Cyan, Magenta, Yellow-Subtractive colors. Some printers may prefer your files be delivered in RGB with ICC profiles attached, as this allows the printer to use color management methods when converting to CMYK.