Final answer:
Ice freezes from the top down in bodies of water, not roadways. Salt is used on roadways to lower the freezing point of water.
Step-by-step explanation:
Ice freezes from the top down because it is less dense than liquid water. This means that bodies of water such as rivers, lakes, and oceans freeze on the surface first. The ice then forms a protective layer that insulates the rest of the water, allowing fish and other organisms to survive in the lower levels. If ice were denser than liquid water, bodies of water would freeze from the bottom up and be lethal for most aquatic creatures.
It's important to note that this principle applies to bodies of water, not roadways. Roadways freeze from the ground up because they are not made of water and do not have the same properties as bodies of water. In colder climates, salt is often spread on roadways to lower the freezing point of water and prevent ice formation.