If you have more than one sheet selected, you'll see [Group] in the
title bar.
Any changes you make, will affect all the selected sheets.
To ungroup, right-click on one of the selected sheet tabs
Choose Ungroup sheets.

Elementary Computer Lab wrote:
Suddenly I'm unable to select any object to reposition it. A white circle
with a slash appears when I move over any object, preventing me from
clicking. I've not seen this before. I also noticed the title bar now has
[Group] added to the title of my document. I'm in the dark as to how to
ungroup, undo, ... and how I got here in the first place.


--
Debra Dalgleish
Contextures
http://www.contextures.com/tiptech.html