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.
Buoyant force is the upward force that keeps things afloat. The buoyant force is equal to the weight of the water the boat displaces. To review buoyancy, have the students explore Buoyancy Basics, on the NOVA Online website.Discuss the diagrams and make sure students understand that the weight of water displaced equals the weight of the wood.ow, distribute the student page Buoyant Boats and the materials listed on that page. Make sure the students understand that they only get one piece of aluminum foil to build the boat. If it tears or gets a hole, they must find a way to repair it.