Intermediate CSS3 and HTML5

What do 6-digit hex codes, rgb(), and hsl() have in common?

A. They're all ways to express transparency
B. They all allow you to express any one of over 16.7 million colors
C. They are all HTML tags
D. They're all ways of handling overflow text in block elements

When used to define opacity in rgba(), hsla(), or the opacity: property, which of the following would be closest to being totally opaque?

A. .1
B. .9
C. .7
D. .4

Which two CSS properties are associated with making an element completely invisible on the page?

A. The opacity: and overflow: properties
B. The display: and background: properties
C. The visibility: and display: properties
D. The visibility: and color: properties

What's the point of putting an invisible element on a Web page, only to turn around and make it visible again in some :hover style rule?

A. To make the element visible only when the user points to something on the page
B. To make the element visible when the page first opens, but then have it disappear after a few seconds
C. There's no point to it. One should never put invisible elements on a page.
D. To make an element visible until the user double-clicks an icon

If you set the height of a block element, like a div, to a certain value, like 100 pixels, then put more content in the box than can fit in that box, the extra content will extend right out past the bottom of the element. Which CSS property would allow you to hide the extra content, or give the user scroll bars to scroll to it?

A. the display: property
B. the overflow: property
C. the box-shadow: property
D. the visibility: property