@Anonymous
I see this is marked solved, but there are many incorrect or misleading statements in this thread.
Scientific (exponential) notation is not a system of units.
It is a method of writing numbers (especially very large or very small numbers).
If you are not familiar with Scientific Notation, I recommend that you shut down AutoCAD for a bit of time and do some research on this as it is probably a pretty important concept in any design field. Even if you never use very large or very small numbers in your work - you should at least instantly recognize when a value is given in exponential notation. To not recognize this can lead to significant errors.
The command -units does not change the document units (except for option 3 or 4) as noted on the command line.
Use the -dwgunits command to set appropriate document units.
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