That's three questions.
No code as to order of cables in the box.
12/3 and a 12/2 might be too tight to fit into one hole, depending on what hole you are talking about... no code restriction here either
Alarm wires should not contact nor be run in parallel or in the same hole as electrical cables.
No code as to order of cables in the box.
12/3 and a 12/2 might be too tight to fit into one hole, depending on what hole you are talking about... no code restriction here either
Alarm wires should not contact nor be run in parallel or in the same hole as electrical cables.