Conservation, sustainable use and protection of (1) _______ resources including plants, animals, mineral deposits, soils, clean (2) _______, clean air, and fossil fuels such as coal, petroleum, and natural gas. Natural (3) _______ are grouped into two categories, renewable and nonrenewable. A (4) _______ resource is one that may be replaced over time by natural processes, (5) _______ fish populations or natural vegetation, or is inexhaustible, such as solar energy.