Final answer:
The problem seeks to find the relative density of metal based on its weight in air and when submerged in a liquid. The apparent loss of weight indicates the volume of the displaced water, which is utilized to calculate the relative density. There seems to be a problem with the question itself or more information is needed, as the calculated relative density does not match any of the provided options.
Step-by-step explanation:
The question given by the student is related to finding the relative density of a metal when weighed in air and in a liquid. Relative density or specific gravity is defined as the ratio of the density of a substance to the density of a reference substance; usually, for liquids and solids, water is used as the reference. The given values are 210 g for the weight in the air and 120 g for the weight in the liquid. Thus, the apparent loss of weight in the liquid is 90 g, which indicates the weight of the water displaced by the metal, assuming that the displaced water's weight is equal to its volume (since the density of water is 1 g/cm3).
Therefore, the volume of the metal is 90 cm3. By using the formula density = mass/volume, we can find the relative density of the metal as follows:
Relative density of metal = (Mass of the metal in air) / (Volume of the metal) = 210 g / 90 cm3 = 2.33 (which is not one of the options given, and the question may have a typo or require more information to answer correctly).