When using the Geospatial Distance Tool with certain files, Acrobat sometimes goes into a busy state (dimmed window, spinning cursor) for long periods of time.

If you wait, it eventually comes back, but it can be a long wait in certain cases. I have two files that cause this problem.

Worth noting: if you turn off 'Path Intersections' in the 2D Snap Settings preference group, the issue still happens, but is greatly reduced.