Which of the following Color Format are a 17 defined colors under CSS 2.1?

Which of the following Color Format are a 17 defined colors under CSS 2.1?

2) Which of the following CSS3 Color Feature can be used as a macro for whatever the current color is?

3) Which of the following Color Format is a CSS3 HSL value with a fourth value to set the alpha channel value for the color to define the opacity of the element?

4) Which of the following Selector selects an element if it’s the only child of its parent with its type?

5) Which of the following Color Format is a CSS2 introduced named color keywords which allows Web page colors to be matched to an operating system’s color use?