Blocks in boxes

This task is about working out volume.
a)


 

 

How many small blocks of the size shown will fill the large box?
 

  (A)
(B)
(C)
(D)
(E)
4
8
12
16
None of these. The answer is __________
 
b)
 
  How many small blocks of the size shown will fill the large box?
 
  (A)
(B)
(C)
(D)
(E)
8
16
20
24
None of these. The answer is __________