Question 848792
The volume of a rectangular prism (a rectangular box) is Length x Width x Height = L*W*H<P>
Double the Length is 2L.  So the new volume is 2L*W*H which is double the original volume.<P>
Let's use a simple example of a rectangular prism with L = 2, W=3 and H=1<P>
V = 2*3*1 = 6.  If the length is doubled to be 4, the volume is 4*3*1 = 12.  It doubles, because a factor of 2 was added to only one of the dimensions.<P>
The new volume is 2L*W*H = 2*Old Volume = 248 cubic feet.