Answer:
it depends which part of the us you are talking about - and by ecosystems do you mean biomes
Explanation:
the us have these following ecosystem
-taiga , hot deserts, cold deserts, tropical dry forests, temperate deciduous forests etc
Answer:
Lithospere is the outer layer that consists of the crust and upper mantel. The asthenospere is right below the lithospere.
Explanation:
Answer:
political system distribution
? Looks like u answered ur self .-.