The answer should be B.
When a solid needs to melt, it must absorb enough heat for first, to raise the temperature, and second, to break the bonding. That's why the particles will have a weaker force of attraction to each other. In liquid, the particles will be more free comparing to solid. This type of heat required is called latent heat in specific. It's the heat required to break bonds, or attract bonds when cooling down.
Note that different materials has different specific latent heat for both melting (including freezing) and condensing (including melting).
Answer:
Conducting experiments and using the scientific method.
Explanation:
Scientists (and other people) test hypotheses by conducting experiments. The purpose of an experiment is to determine whether observations of the real world agree with or conflict with the predictions derived from a hypothesis. If they agree, confidence in the hypothesis increases; otherwise, it decreases.
Answer:
Both plant and animal cells comprise membrane-bound organelles, such as endoplasmic reticulum, mitochondria, the nucleus, Golgi apparatus, peroxisomes, lysosomes. They also have similar membranes, such as cytoskeletal elements and cytosol. The plant cell can also be larger than the animal cell
Answer: The periodic table
Explanation: Demetri Mendeleyev is famous for developing the periodic table. He introduced it in 1869.