The difference between mass and weight is that mass is the amount of matter in a material, while weight is a measure of how the force of gravity acts upon that mass.
Explanation:
Mass is the measure of the amount of matter in a body. Mass is denoted using m or M. ... Weight is mass multiplied by the acceleration of gravity (g).
The answer is D. Solutions you cannot see the separate substances. however in a mixture you can see the different substances. So the correct choice is D