Folded measurements

This task requires find the dimensions of pieces of paper when they are folded.

shape 1                               shape 2                  shape 3  

 
Jason took a square piece of paper (shape 1). He folded it in half to get shape 2 and in half again to get shape 3.
 
a) What are the measurements of the piece of unfolded paper Jason started with (shape 1)?
 
  (A)
(B)
(C)
(D)
(E)
40 cm × 20 cm
30 cm × 30 cm
40 cm × 40 cm
60 cm × 40 cm
None of these. It measures __________cm × __________cm.
 
b) If Jason folded the smallest piece of paper (shape 3) in half again, what would its measurements be?
 
  (A)
(B)
(C)
(D)
(E)
10 cm × 10 cm
15 cm × 15 cm
15 cm × 10 cm
20 cm × 10 cm
None of these. It measures __________cm × __________cm.