Newbie question

I've got a small home business with 3 desktop pc's & 2 laptops.  1 desktop is running windows 7 home premium the other 2 desktops are running xp pro 64 bit.  The 2 laptops are HP & running windows 7.  Right now we are running 3 different products for internet security.  Can I run Norton internet security 2011 on all the machines?