The Show Dimension Text option on the General tab of the Dimensions dialog box determines whether dimension units are shown or hidden. Select this option to show the units. Deselect this option to hide the units.
The currently selected units setting appears in the Units button. Click this button to change this setting.
The Precision list box shows the current decimal precision of the dimension units. To change this setting, click the down arrow next to the box.
The Prefix and Suffix text boxes let you enter text to appear before and after the units of a dimension line.
The Show Extension Lines option determines whether extension lines are shown or hidden. Select this option to show extension lines. Deselect this option to hide extension lines.
The Gap box specifies the amount of space between the points measured by a dimension line and the start of its extension lines.
The Extension box specifies how far extension lines protrude beyond a dimension line.
The Use Outside Arrows option determines whether dimension lines show arrows pointing outwards or inwards.
The Arrow Length box specifies the length of outside arrows.