Not a 100% sure but i believe it’s B
Answer:
The appearance of free oxygen in the Earth's atmosphere led to the Great Oxidation Event. This was triggered by cyanobacteria producing oxygen which developed into multicellular forms as early as 2.3 billion years ago
Explanation:
To clarify what I said here are some questions to help!
How did oxygen first appear?
Whiffs in the air is how oxygen first appeared billions of years ago.
For the most part, scientists agree that oxygen, though lacking in the atmosphere, was likely brewing in the oceans as a byproduct of cyanobacterial photosynthesis as early as 3 billion years ago
When was oxygen found?
2.33 billion years ago
Since its first appearance 2.33 billion years ago, oxygen accumulated in high enough concentrations to have a weathering effect on rocks just 10 million years later.
I don't know if this helped you but if it does, please let me know!
Calculate the average metabolic rate of a 65-kg person who sleeps 8.0h, sits at a desk 6.0h, engages in light activity 6.0h, watches TV 2.0h, plays tennis 1.5 h, and runs 0.50h daily, If the metabolic rate for sleeping is 70 J/s, for sitting is 115 J/s, for engage in light activity is 230 J/s, for watching TV is 115 J/s, for playing tennis is 460J/s and for running is 1150 J/s.
Answer:
171.8 W
Explanation:
The Average metabolic rate can be deduced by multiplying each entity performed at a some particular hour of time with their corresponding energy, all divided by 24 hours.
Average metabolic rate = 
= 171.8 W
Explanation:
Typical roots contain three different sections, or zones: the meristematic zone, the zone of elongation, and the zone of differentiation. In the meristematic zone, named after the apical meristem, the plant cells undergo rapid mitotic division, creating new cells for root growth.
