A plank 2.00 cm thick and 15.8 cm wide is firmly attached?

A plank 2.00 cm thick and 15.8 cm wide is firmly attached to the railing of a ship by clamps so that the rest of the board extends 2.00 m horizontally over the sea below. A man of m 92.5 kg is forced to stand on the very end. If the end of the board drops by 5.10 cm because of the man's weight, find the shear modulus of the wood.