Density is a measure of how much what there is in a volume of a substance

Density is defined as the relationship between the mass and volume of a substance

Explanation:

Density is defined as the relationship between the mass and volume of a substance. A unit of measurement can be g / ml. The greater the mass of the substance, the greater the density value

the national environmental policy act (nepa) is a united states environmental law that promotes the enhancement of the environment and established the president's council on environmental quality (ceq). the law was enacted on january 1, 1970. to date, more than 100 nations around the world have enacted national environmental policies modeled after nepa.

i think its the first one