The thin metallic strip of vernier callipers moves downward from top to botton in such a way that it just touches the surface of beaker. Main scale reading of calliper is 6.4 cm whereas its vernier constant is 0.1 mm. The `4^(th)` of vernier scale division is coinciding with main scale division. The actual depth of berker in mm is (when zero of vernier coincides with zero of main scale)

Options

A. 6.64 cm
B. 6.42 cm
C. 6.44 cm
D. 6.13 cm

Answer

c