Help me out: Tuning

Thanks, whats a decent box building program, I tried going to RE's site but I had no help

Ok, how do you find out the volume of a box that has 4 different sides? I forgot what you call it but its not a rectangle or a square...//content.invisioncic.com/y282845/emoticons/redface.gif.62fdbfe1a101588a808c4cff71bcb942.gif

There is the inside the piece on the left and the right will overlap.

I need it 4 cubes at 35 hz, this isnt exactly my first but might as well be.

If you feel like helping have at it.. Thanks

I just looked at it and I am sure you guys are confused as hell, I dont even know what I am doing.. My subs will face the seat and the port will go out of the side towards the side of the truck..

Well to make it easier, I can figure it tom but how do you find out the volume of a shape like that?