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2.Using the line numbering display in the gutter margin, you can select an entire line, a block of lines, or all the lines.
3.To adjust the spacing within(lines in a document, for example), so that the lines end evenly at a straight margin.
4.Style sheets, on the other hand, handle issues of presentation: fonts, colors and margins.The intent is to simplify sites, decrease download times and more easily present the same content to multiple types of devices.
