Which statement accurately describes the relationship between elements and reactivity? A. Elements whose atoms have a filled outer energy level are the most reactive.
B. The most reactive elements are those whose atoms hold tightly onto all of their
electrons.
C. The most reactive elements are those whose atoms can easily lose or gain valence
electrons because they have unfilled valence shells.
D. The most reactive elements are those whose atoms have no valance shell.

For a to be healthy, it has to have lots of different kinds of plants and animals. all of the different types of plants and animals in an ecosystem. name four types of ecosystems from those listed in the video. b) c) d) most living things live here. all living things depend on how an ecosystem like a game of sticks? why should we build new buildings on existing land? name four extinct species from those listed in the video. b) c) d) the best way to wipe out a species is to the largest ecosystem in the world is this percent of the world is covered by water. how many of all species in the world live in the ocean? list five things you can do to increase biodiversity. b) c) d) e) how many species are we losing per hour?

Which of these is an example of land degradation? a. containers designed to store pollutants leak. b. fertilizers provide too many nutrients to crops. c. garbage is buried so the land can be reclaimed later. d. a drought kills all the plants in an area, leaving bare land

How dose plate tectonics effect climate