To find the volume of a Prismatic Rectangle you must multiply all three sides together. In your case, It would be 4 x 2 x 1. Which would leave you with an answer of 8.
The formula for a rectangular prism is l x w x h. l=lenght w=width h=height (it does not really matter how you out them in order the height can be first because the answer will be just the same no matter what order you out them) so therefore the are would be 4 x 1 x 2=8. It
