Answer:
something around 2-3
Step-by-step explanation:
I saw that 5 and 3 made a big space and if that wide of a place is 40cm if you had to add 10 more then I'm pretty sure 2-3 would make the most sense considering your multiplying 2x(the number you pick in this situation 2 or 3) would be a lot already 2x2=4+10=14 which might be already enough. your choice.
