The answer is D) carbon forms both single and double bonds.
heterotrophs energy comes from the sun
Answer: Heart Rate
Explanation:
When you are running in a race, one feedback mechanism that happens as you increase exercise and muscle activity is that, your heart rate also increases. Your heart rate increases because it needs to sustain the body's need of more energy to be supplied to the different parts of the body during an activity.
Answer: D I’m pretty sure
Explanation:
Answer: the earth was just starting to develop really well and well enough for life.
Explanation: atmospheric oxygen and oceanic calcium levels went up, but nobody needs to know that much facts about how earth developed, But the group called phyla started growing because of these conditions