Answer: the formula for volume for a rectangular prism is length times width times height, so the volume of this shape can be broken down into the shapes that make it up. A triangular prism and a rectangular prism, for triangular you do the same thing but at the end divide by two.
Rectangular:
6x3x4=72
Triangular:
4x6x3=72 but divide that by two and you get 36
Final solution:
36+72=108