Why should we protect an entire ecosystem and not just one species?

Which property is used to identify the origin of an igneous rock? color density hardness crystal size

What can be said about farmers in highly developed countries? a) they have little or no negative impact on the environment. b) they practice subsistence agriculture. c) they are able to incorporate polyculture into their farming practices. d) they utilize organic farming techniques on a regular basis. e) they rely on large amounts of energy from fossil fuels.

Math focus 4. calculate a map has index contours at 250 m, 500 m, and 750 m. what is the contour interval?