Final answer:
In 'j,' the layers of Earth are classified based on density, while in 'I,' the classification is done based on physical properties. Density is an intensive physical characteristic that helps identify substances and remains constant across sample sizes.
Step-by-step explanation:
In 'j,' the layers are based on density, while in 'I,' the layers are based on physical properties. Density is a physical characteristic of matter, particularly it's an intensive property meaning it does not depend on the amount of material present. Each substance has a unique density that helps in identifying the substance. It's an inherent property that remains constant regardless of the sample size. For instance, water has a density of 1 g/mL, which will be the same whether you have a glass of water or a pool full of water.
Earth's interior can be categorized by density or physical properties such as whether layers can move in a rigid or 'plastic' manner. Density provides not only a clue to a substance's identity but also to its phase and substructure, with denser states like solids and liquids having particles in close contact, as opposed to less dense gases where particles are separated by larger spaces. Physical properties include various attributes like appearance, conductivity, hardness, and include states of matter such as solids, liquids, and gases.