Quadrilateral. In Euclidean plane geometry, a quadrilateral is a polygon with four sides (or 'edges') and four vertices or corners. Sometimes, the term quadrangle is used, by analogy with triangle, and sometimes tetragon for consistency with pentagon (5-sided), hexagon (6-sided) and so on.
Some environmental scientists and specialists focus on environmental regulations that are designed to protect peopleâs health, while others focus on regulations designed to minimize societyâs impact on the ecosystem.
Animal science is the study of animals that live alongside humans. Around the world, humans rely on animals for food, fiber, labor and companionship. Animal scientists help us understand and manage these animals. Animal scientists work with farm animals, wildlife, laboratory animals, pets and zoo animals. They study these animals to help keep them healthy and productive. Animal scientists help put food on our tables. Animal scientists work with farmers to improve animal breeding, growth and nutrition.