Answer:
The main reason why mountains are rarely populated is because of the harsh climate that are dominating in those areas. On the other side, another important reason is that mountainous areas are not fertile enough and people are not able to grow crops. Lack of resources therefore is obliging people to move from the mountains to lower terrains.
Explanation:
Because of the mentioned reasons most of the people since the beginning of civilization were inhabiting river valleys and the areas that have better climate.
For example, Chinese civilization developed in the valley of Yangtze and Huang He and not Himalayas.
Answer:
ponds cooler than 20 °C
Explanation:
There is great effect of temperature on the dissolved oxygen in a pond water,
When the water is hotter it will hold less oxygen but when the water is cold it will holds more oxygen. Therefore, ponds cooler than 20 °C will will have a higher average oxygen concentration.
More than 2/3 of Central America's agricultural land is used for cattle grazing.
Answer:
Option: a. 200 million years ago
Explanation:
Million years ago, Earth had one supercontinent called Pangaea and surrounded by an ocean (Panthalassa). Alfred Wegener proposed the concept of one big continent after putting together different records of confirmation. He was able to give his theory by examining fossils of plants, trees, animals, and reptiles that found in different continents. About 200 million years ago, the supercontinent began to split up into two parts; Gondwana from Laurasia. Today's countries, including Africa, Antarctica, India, South America, and Australia are part of Gondwana, where Europe and North America from Laurasia.
