Answer:
The first human ancestors appeared between five million and seven million years ago, probably when some apelike creatures in Africa began to walk habitually on two legs. They were flaking crude stone tools by 2.5 million years ago. Then some of them spread from Africa into Asia and Europe after two million years ago.
Answer:
The answer is letter A.
Explanation:
During anaerobic respiration, lactate levels increase when muscles cells need more energy, however muscles cells eventually fatigue, thus athletes should modify their activities to increase aerobic respiration.
Answer:
reduce exposure to foreign substances. humidify and warm inhaled air. increase air flow to arteries, veins
Answer:
When magma cools underground, it cools very slowly and when lava cools above ground, it cools quickly. When magma and lava cool, mineral crystals start to form in the molten rock. Plutonic rocks, which cool slowly underground, have large crystals because the crystals had enough time to grow to a large size.
Explanation:
It basicly startes to molden the rock, and more.
