Answer:
2.7 billion
Explanation:
This period is referred to as the Great Oxygenation Event. This period saw the evolution of photosynthetic organisms (cyanobacteria) that utilized carbon dioxide (that dominated the atmosphere then) and sunlight to manufacture their energy molecules-glucose. Photosynthesis produces oxygen as a byproduct that is evolved into the atmosphere. As these photosynthetic organisms proliferated on earth, the atmosphere composition changed to become partly dominated by oxygen (which is an oxidaton agent) with less and less carbon dioxide.
Answer:
(carbon dioxide, water and sunlight)
Explanation:
Answers; After a car is turned on, the engine becomes hot. ...
A radiator is a good example of conduction. ...
You can warm your back muscles with a heating pad.
Roasting wieners over a campfire is fun until the heat from the fire is conducted up the coat hanger to your hand.
a group of single-celled eukaryotes.
Answer is b hole this helps