Why does spreadsheet automatically open
 

I created a spreadsheet and saved it with it's own file name of RRR. Now
whenever I split my screen to horizontal view, even when that speadsheet is
closed, it automatically opens, why would that be? It seems to only happen
when I have two other documents opened, split my screen, then I have 4
spreadsheets...the original 2 I had open, personal.xls and RRR.xls. Thank
you for your help.