Answer:
1160cm squared
Explanation:
as for me I've calculated the surface area of a closed cuboid.
this is because we are not informed whether it is open or closed.
and so my teacher told me that if you're not informed, if a cuboid is open or closed, just assume that the cuboid is closed.
and that is what I have done.
hope it helps.
in case of any questions feel free to ask.