Answer: a Volcanoe
What it is are openings, or vents where lava, tephra (small rocks), and steam erupt on to the Earth's surface.
I believe T, hope this helps!
Due to decreased light penetration, B. THE MOUTH of the rivers and streams will have less diversity of plant life.
The decreased light penetration is brought about by the murkiness of the water due to numerous deposits of sediments. Sediments that have been collected at the water travels towards the mouth of the rivers and streams causes the water to be muddy and murky making it impossible for light to penetrate.
The U.S economy produce 20% of the world's output
The answer is steamboats! The first steamboat came year 1807 and was invented by John Fitch:)