A rectangular glass block of thickness 9cm is placed on a newspaper. Find the apparent length and shift in letters. 
a) Apparent length = Actual length, Shift = 9 cm 
b) Apparent length = 9 cm, Shift = 0 cm 
c) Apparent length = Actual length - 9 cm, Shift = 0 cm 
d) Apparent length = Actual length, Shift = 0 cm