Which of the following correctly ranks these three categories from least dense to most dense?

Question

A.
Earth's crust, human beings, Earth's atmosphere
B.
Human beings, Earth's crust, Earth's atmosphere
C.
Earth's atmosphere, human beings, Earth's crust

Answer 1

To rank the three categories from least dense to most dense, we need to understand the general densities of each:

1. Earth's atmosphere - The atmosphere is very low in density compared to solids and liquids, with air being less dense than water.
2. Human beings - The density of human beings is generally higher than that of air. People are mostly made up of water, which has a density of about 1 g/cm³, leading to a density around that range.
3. Earth's crust - The Earth's crust is made up of rocks and minerals that are much denser than both air and human bodies, with an average density typically around 2.5 - 3 g/cm³.

By this reasoning, the correct ranking from least dense to most dense is:

C. Earth's atmosphere, human beings, Earth's crust.