A regular block of wood floats in water with 60 mm projecting above the water surface. When placed in glycerin of S.G. = 1.35, the block projects 85 mm above the surface of chat liquid. Determine the...

A regular block of wood floats in water with 60 mm projecting above the water surface. When placed in glycerin of S.G. = 1.35, the block projects 85 mm above the surface of chat liquid. Determine the S.G. of the wood.

What length of80 mm by 310 mm timber (S.G. = 0.50) will support a 445 N man in salt water (S.G. = 1.025) if he stands on the timber.