[AccessD] Run External App from within Access

I'm having a senior moment here today, folks. I cannot remember how to run
an external app from within Access. In this case it's a batch file.

Followup question.... Is there a way to specify an exit level (i.e.
errorlevel) when exiting an Access app? Suppose for example that Access is
being invoked from a batch file, and that I want to set an errorlevel of 1
or 0, then take action on this value in the batch file.

I.e.

MyBatch.cmd:
'run a simple Access app
MySimpleApp
'test its exit value
If errorlevel = 1 goto One
If errorlevel = 0 goto Done

:One
Rem Do something cool

:Done
Rem Do nothing at all


TIA,
Arthur