giving brainiest :) ^^

Answer:
78
Step-by-step explanation:
I think its 78 because for the top 2 cubes on the top I did one 2cm for one side then there are 8 sides in a cube so I did 2x8=16 and the cube below that is the same so that's also 16 then I did 16x2=32 so the green cubes are 32 and the big blue has 8sides as well each side is equal so 2+5+5+11=23 and there is two of them each next I did 23x2=46cm and finally do 32+46=78cm I hope that the right answer I don't know for sure make sure to check for sure hope this helps.