The plot thickens.
I e-mailed the file to a friend who has full Acrobat. He opened it but the edit tools (i.e. highlight, which I needed) would not work. He got some kind of error message about not being able to edit the image.
I made this file by using HP Scanning Software version 4.5 which has no setting for specifying the type of PDF other than things like resolution, sharpness, etc.