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).
CMYK (Cyan, Magenta, Yellow, Key or blacK) is subtractive because the paper where its printed on is white and the ink subtracts from the brightness of the white paper. CMYK also uses secondary colors that are much lighter than those used in RGB because to reproduce the darker colors, you would only need to add more ink.