World War I and II. These wars caused lots of economic growth and development because there was a pressure to create better inventions. Having better technology could mean the win or lose of a war. :D
Geographic location refers to a position on the Earth. Your absolute geographic location is defined by two coordinates, longitude and latitude. These two coordinates can be used to give specific locations independent of an outside reference point.
Two questions which arises in my mind about aurora borealis are:
- Why does aurora borealis occur?
- Why does aurora borealis occur in a particular time of the year?
Answers:
- As solar wind approaches the Earth, it meets the Earth's magnetic field. In the ionosphere, the ions of the solar wind collide with atoms of oxygen and nitrogen from the Earth's atmosphere. The energy released during these collisions causes aurora borealis.
- Aurora borealis is active the whole year. Since it needs to be dark in order to see aurora borealis in the sky, late August/September through the very beginning of April is the best time to go to a destination located in the aurora zone for a chance to see them.
Note: These are the questions which arises in my mind only. It may differ from person to person.
Hope you could understand.
If you have any query, feel free to ask.
The Mayan and other Mesoamerican cultures used a vigesimal number system based on base 20 (and, to some extent, base 5), probably originally developed from counting on fingers and toes. The numerals consisted of only three symbols: zero, represented as a shell shape; one, a dot; and five, a bar.
Omaha and Sacramento is the answer
