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.
What Environmental Scientists and Specialists Do. Environmental scientists and specialists use their knowledge of the natural sciences to protect the environment and human health. They may clean up polluted areas, advise policymakers, or work with industry to reduce waste. Duties. Environmental scientists and specialists typically do the following: 1  Determine data collection methods for research projects, investigations, and surveys. 2  Collect and compile environmental data from samples of air, soil, water, food, and other materials for scientific analysis.
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.