The subject of this question is Physics, and it involves understanding the concepts of mass and weight. The question asks for an explanation on how to calculate the mass of a solid given its weight in grams. The mass can be found by multiplying the weight by 10^-3 kg/g.
Step-by-step explanation:
The subject of this question is Physics. The question is related to the concept of mass and weight. Mass refers to the amount of matter that an object contains and is measured in kilograms. Weight, on the other hand, is the force exerted on an object due to gravity and is measured in newtons or pounds.
In the given question, it is mentioned that the weight of the solid in air is W (grams weight). To find the mass of the solid, we can multiply the weight by 10-3 kg/g to convert it to kilograms. So, the mass M = W x 10-3 kg.