Answer:
I believe the answer is 60.
First, I found the sides for each of the boxes, and pictured folding the box net into a 3D shape. Next, I found out that the top of the box was the box labeled with the 10 inches. Last, I found out that the side length of that box was 6, then I multiplied to get 60.
Im sorry if this is wrong, I do not know what the surface area is.
But I really hope it helps! TYSM! ;)
