Answer:
Blood is carried away from the heart by arteries. Blood that is rich in oxygen. Blood that is low in oxygen is returned to the heart by veins. there is more pressure in arteries than in veins.
Answer:
A
Explanation:
The kingdom is the least specific classification of living things, so it therefore encompasses the largest variety of organisms
Answer:
Many small organisms can be preserved within these layers of sediment through time. The changing abundances of these fossils through time can tell us whether a change in the environment or climate was gradual or abrupt. Studying fossil pollen and other fossils helps scientists to learn more about climate change.
