In the fixed-width layout the page and columns _____. 1. are set to a certain width using the percentage values 2. expands and contracts to fill the entire screen 3. are set to a certain width using pixel values 4. none of the above What is missing in the following code: p.opening first-line {? 1. nothing is missing 2. semicolon after first-line 3. colon before opening 4. colon between opening and first-line Classes can either be _____. 1. dependent or independent 2. static or dynamic 3. varied or unvaried 4. finite or infinite What is wrong with the following code: @import url(header.css) 1. the file extension is not needed 2. @ symbol is not needed 3. everything is syntactically correct 4. semicolon at the end of the statement is missing