You can measure a 3D model only if the PDF creator enables the functionality for Reader users.
The 3D Measurement Tool is set to automatically display the most likely measurement, but you can choose a different measurement type.
You can add comments to a 3D model only if the PDF creator enables the functionality for Reader users.
You can add comments to an existing comment view by selecting that view in the Model Tree before you click in the model.
The Comments List shows all the comments in a PDF. When you select a comment, the PDF scrolls to the comment in the document pane.
Click Expand All or Collapse All . To expand or collapse individual comments, click the plus or minus sign next to the comment.
Click Next or Previous .