The volume of a prism is V=lwh or Bh where B is the area of the base (l x w) and h is the height.
If the base area and height are both doubled, the volume is increased by a factor of 4.
To prove this, let
V = Bh
B1 = 2B
h1 = 2h
V1 = B1h1 = (2B)(2h) = 4Bh = 4V
Hope this helps.