Over time, a stream tends to increase in length by eroding and extending its channel upstream, in a process called .

Why did macarthur want to invade china? why did truman oppose this?

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

In the following diagram, four different index fossils are labeled: which of the labeled fossils comes from the oldest organism? a b c d