I neeed help please

Eristics do scientists use to distinguish between organisms in different kingdoms

What is the importance of having the us forest service, the bureau of land management, the us fish and wildlife service, and the national park service? to manage land resources for conservation and the development of natural resources to manage land resources for conservation and the development of urban areas to preserve historical landmarks and manage the development of urban areas to preserve historical landmarks and manage the development of rural areas

Veins have a much lower blood pressure than arteries. which of these prevents backflow of blood in veins? a. pressure applied by the heart b. one–way valves in veins c. thin muscular walls of veins