I need helppp!! This is confusing !

9

Step-by-step explanation:

So the little arrows on the lines means they are equal to each other so if you look, A to D and B to C have only one arrow meaning those two lines are the same lines

and A to B and D to C have two arrows meaning those two lines are the same

so that means if A to B is 9 and it's equal to the line D to C, then D to C is also 9

Hopefully this wasn't too confusing

this is answer of 144 cubic meters