A wooden plank ( sp. gravity = 0.5) of 1 m $$\times$$ 1m $$\times$$ 0.5 m floats in water with 1.5 kN load on it with 1 mx 1m surface horizontal. The depth of plank lying below water surface shall be

A

0.178 m

B

0.250 m

C

0.403 m

D

0.5 m