When standing in a stream bed, you observe identical layers of sedimentary strata on both sides of the bed. which came first, the sedimentary rocks, or the stream? explain your reasoning, including what principle you are using.

answer; native americans who sometimes actively impeded railroad construction; physical obstacles like rivers and canyons, and

land

explanation:

australia is the flattest continent, and it has vast plains.

the correct answer is d.) many new life-forms appeared, including most of the known types of invertebrates. hope this