Three characteristics that are unique to mammals include their  ability to feed their babies with milk made in their mammary  glands. Mammals also have hair on their bodies â¦and they have a  single bone that makes up their lower jaw.
buoyancy. n. 1. the ability to float in a liquid or to rise in a fluid. 2. (General Physics) the property of a fluid to exert an upward force (upthrust) on a body that is wholly or partly submerged in it. 3. the ability to recover quickly after setbacks; resilience.
The buoyancy force on the oil is equal to the weight of that 1 cubic cm of water. Oil is less dense than water, so 1 cubic cm of oil weighs less than 1 cubic cm of water. Therefore, the upward buoyancy force on the oil, which is equal to the weight of water displaced, is greater than the downward force of gravity on the oil, also known as the weight of the oil. This inequality of forces causes the oil to rise in the water. If the oil were denser than the water, the oil's weight (the downward force) would exceed the buoyancy force (the upward force), and the oil would sink in the water.