given- cube of side 20 cm and density 650 kg cubic meter. To find- distance -from the water level

The buoyancy force balances the weight of the cube.

ρ_sV_sg = xρ_wV_sg,

where x is the volume fraction submerged in water, and other symbols have usual meaning.

x = ρ_s/ρ_w = 650/1000 = 0.35

V_submerged/V_s = 0.35

Ah/0.2A = 0.35, where h is the height of cube submerged in water.

h = 0.07 m = 7 cm.

So  13 cm would the So called distance from water level.

Regards,

Team,

TopperLearning.