a piece of wood of volume 200cm3 and density of 1.05gm/cm3. what volume of wood would remain above the surface of the liquid

3 answers

None, sinks
That density is greater than fresh water, typo?

mass = 1.05 *200 = 210 gm

so Archimedes says mass of water displaced = 210 gm
but water(fresh, out of my geography) is 1.00 gm/cm^2
so
210 g = 1.00 * V of water
V of water = 210 cm^3 of water displaced, we need a hunk of styrofoam :)
I am reminded of the stern tube bearings on the battlship IOWA, when we pulled the shafts to reactivate. The stern tube bearings were made of water lubricated Lignum vitae( is a wood), also called guayacan or guaiacum. Look up the density of that wood. http://www.engineeringtoolbox.com/wood-density-d_40.html
We replaced all that wood with oil lubricated bearings. I still have a piece of that wood bearing on my desk.
As far as I know lignum vitae is still used for many stern tube bearings, although probably no longer by the Navy.