<u>Stromatolites are layered mounds of calcium carbonate that were deposited by algae during the Precambrian time.</u>
Answer: Option C
<u>Explanation:</u>
Stromatolites are the deposit of the layer which is mostly of limestone and these are mainly formed by the blue green algae which are only one celled organism of primitive times.
The features of these are that they are normally thin and have layers that might be either light or dark in color and are either flat or some of them even have a shape of a dome.
The answer SHOULD be D, if I'm wrong, I really am sorry.
<h2>Pull factors are the reason why groups of people move to a particular place.</h2>
Explanation:
Those factors that attract group of people to leave their home and move to a particular destination is called as Pull factors.
Better job, culture, political, climatic and more financial opportunities, and the desire to get a better life are the reasons to attract people into new place.
The ideas and realizations about a particular places may not be always correct, but the strong pull factors forces the individual to move to a new destination.
After the retirement, many elderly people look for warm weather, peaceful and comfortable places to spend their rest of the life. These ideal places are referred as pull factors.
The U.S economy produce 20% of the world's output
The Mekong River flows through the countries China, Myanmar, Thailand, Laos, Cambodia, and Viet Nam.
