Answer:
Existence itself is not homogeneous. It is heterogeneous. That means there are various kinds and degrees of purity.
I know jobs for one, over population maybe, and because they are worried that dangerous people could be entering into the country with intention to harm. (unless this is a "only 3 right answer" kind of thing)
Answer:
Areas or regions with low sea level or at sea level are called lowlands.
Lowlands are formed by deposition of lava through water, wind, or soil erosion and it has been said that such plains are more fertile for farming as compared to other high sea-level plains.
At Lowlands, people get opportunities for employment and the economy of the nation can be boosted.
For example, Lowlands of Scotland.
Farmers growing paddy or rice are getting the main benefits of Lowlands.
Lowlands have a suitable environment for many agricultural products.
Farmers can develop dairy farms and mountain farms.