39in³ is a required volume.
Solution given:
for upper one
length[l]=8in
breadth[b] =3in
height[h]=1in
now
volume [V1]=l×b×h=8×3×1=24in³
again for lower one:
length[l]=6-1=5in
breadth[b] =3in
height[h]=1in
volume [V2]=l×b×h=5×3×1=15in³
Again
total volume =V1+V2=24in³+15in³=39in³
