To Create Ordinate Dimensions
1. Establish the baseline by clicking > 
Baseline.
Baseline.2. Select the geometry to dimension as a baseline and then middle-click to place the dimension.
For lines, the baseline is oriented the same way. For arc and circle centers, and for geometry endpoints, choose one of the following options from the Dim Orientation menu:
◦ Vert—Orient the baseline vertically.
◦ Horiz—Orient the baseline horizontally.
3. To create ordinate dimensions to the specified baseline, click > 
Normal.
Normal.4. Select the baseline dimension and then select one or more entities. Middle-click to place the dimensions.