0.88 g/cc is most likely to be the density of the iceberg. This is because the tip of the iceberg remains on the top of the water hence the density must definitely remain on the top of the water. Density, also known as the volumetric mass density, is the mass per unit volume of a mass.
The general formula for the density is given as density = mass over volume. The density of the material changes with the temperature and pressure. For solids, this is quite a small change however the change is very significant for the gases or liquids.