Question

a wooden block of density 860 kg per metre cube at zero degree celsius is floating on benzene liquid of density 900 kg per metre cube at zero degree celsius the temperature at which the block just submerge in Benzene is

Answer 1

So the question is what temperature does benzene have a density of 860kg/m^3?

the density of a fluid may be expressed as
rho= rho_o/(1+ Beta(t_f - t_o)

for benzene, at t_o, rho is 0.8756 g/cu cm at 20 deg C, and beta is 0.00121999997646 measured at 0 degC

.860=.876/(1+0.00121999997646(Tf-0C)
solve for Tf