A certain spring scale measures the weight of an object hanging from it by measuring the force exerted on the scale's spring by the object. The weight of a block of wood hanging in the air is measured by the scale to be N1. When a lead sinker is hung from the piece of wood and dipped into a beaker of water, without touching the walls of the beaker, the combined weight of the wood and sinker is measured by the scale to be N2. When the wood and lead sinker combination is completely submerged in the beaker of water, again without touching the walls of the beaker, the weight is measured by the scale to be N3. The density of water is about 1 g/cm^3, about what is the density of the wood measured in g/cm^3?