They <span>are determined by the mean annual temperatures and precipitation. With a little less rain the </span>steppe<span> could easily turn into a </span>desert<span>. More rain and it would be classified a prairie.</span>
The answer is c
Reason: that’s what happens when the hit hits plants. That’s how they eat
i would say D. ! :) let me know if this is correct
<u>Answer:</u>
Cyanobacteria start producing pure oxygen around 200 million years ago.
<u>Explanation:</u>
Many scientists believed that Earth did not have any oxygen. Cyanobacteria or the blue green algae are the microbes which produced oxygen for the first time with the help of photosynthesis. This was around 4.5 billion years ago: after Hadean eon.
They were very simple, but they produced oxygen in the early earth’s atmosphere. So, they brought evolution on earth. This “blue-green algae” exists in salt water, rocks and soils and play a major role in maintaining the ecosystem.