<u>Answer:
</u>
The build-up of three oxygen created our ozone layer around two billion years ago.
<u>Explanation:
</u>
- The ozone layer is a part of the stratosphere which is located right after the troposphere in the atmosphere of the Earth.
- The ozone gas is made up of the abundance of three oxygen molecules combining with the ultraviolet radiation emitted by the Sun.
- The development of the ozone layer happened around two billion years ago when the oxygen concentration levels on the planet began to rise slowly and gradually.
The Country which is surrounded by water on all sides are known as "Islands" and there could be many examples like: "Britain, Ireland" etc..
Hope this helps!
Answer:
Movement of people between places on a regular basis → cyclical migration
Study of population → demographics
average number of children a woman will have in her lifetime → fertility rate
the number of people who live in a square mile or kilometer → population density
people who leave their homelands seeking safety in a foreign country → refugees
Explanation:
Migration is the movement of people from from one place to another. A cyclical migration is a kind of movement that is a routine and are usually short.
Demographics is the study of population base on age , race, gender etc.
fertility rate is said to be the measure the number of life birth of a woman in a specific period of time . Fertility rate gives information on how fertile a woman is.
Population density is the number of people per unit area. It gives information on the population per geographical area.
Refugees are individual that have been forced to live their countries to seek refuge in another country as a result of violence or persecution.
If I correctly understand your question, the first coordinate "29°N 98°W" is located in the following:
City: Falls City
Country: United States
Continent: North America
An for the second coordinate "19°N 99°W:"
City: Tlalnepantla
Country: Mexico
Continent: North America