the answer to this question would be D or 1512.
to solve this question, you find the volume of each prism.
to find volume, you do length times width times height.
the top prism would be 15 times 12 times 6 which would be 1080
the bottom prism would be 6 times 12 times 6 which would be 432.
you add the volumes of the two prism or 1080+432= 1512.
hope this helps! :)