the density of a gas一种气体的密度Mercury has a much greater density than water.水银的密度比水大得多.Astronomers know that Pluto and Triton have nearly the same size, mass, and density.天文学家知道冥王星与海卫一拥有几乎相同的体积、质量与密度。...
The zero point of the density scale is defined by having no specimen in the densitometer.定义密度计内设有样品时的密度为密度尺标的零点.Once again, illustrators exposure sites in order to achieve the optical density at least version 4.00.再不主, 不...