Warm, dry air. Hope this helps
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.
The most appropriate answer would be magma. Lava is a magma that reaches the Earth's surface, which is technically it is also a magma, and magma is located below the Earth's surface.
Lava at Earth's surface or magma below Earth's surface cools and harden to form mineral crystals.
A cold front is the transition zone where a cold air mass is replacing a warmer one, (They move more slowly than warm front's.) Others are Characteristics of cold front's and they move faster than warm.
Hope this helps<3