In siberia, the act as oil pipelines.

railroads

rivers

trucks

highways

Impressions of tropical swamp plants were observed on rocks in polar regions. the impressions were dark black imprints, which means the fossils are examples of ( 1 ) the fossils tell us that polar regions ( 2 ) ( 1 ) a. carbonization b. mineralization c. trace fossils ( 2 ) a. had tropical plants that can grow in ice b. might have had a diffierent climate in the past c. will have abundent vegitation

The layers of earth are based on what two sets of characteristics?

Based on the information in the graph, what can you conclude about humans in the world in general?