Measuring

Measurement Units

Sets unit of page dimensions given in the status bar and the Print dialog box. The unit can also be applied as the default setting for measurement if you specify it before using the measure commands. (Tip: The unit defined in the Format tab in the right panel prevails over the preference settings. If you do not set the measurement unit before using the measure commands or change the unit in the Format tab during the measurement, the unit specified in the Format tab will be used as default instead.)

Measurement Label 

Choose to use the default measurement label or specify your own label.

Measurement Markup 

Use Default Leader for Distance Measurement: Specify whether to show the line leader on both sides of the measurement points or not while measuring the distance. 

Use Scale and Units From Document (When present)

Select the option to use the scale and units embedded in the document, if any. Deselect the option to specify the scale and units manually. The option is unselected by default.