Answer:
Photosynthesis.
Explanation:
Photosynthesis may be defined as the process by which the plants prepare their own food by the use of sunlight and chlorophyll. The light energy is converted into chemical energy for food storage.
The early environment of the Earth's atmosphere is highly reducing. The photosynthesis at an early environment causes the formation of the traces of oxygen. The water molecule will breakdown into the hydrogen and oxygen by the use of the ultraviolet light.
Thus, the answer is photosynthesis.
Number 1:4
number 2: 3
number 3: 1
Coating of mucus( gastric mucosal barrier) protects the stomach from its acid
Answer:
These are the three that exceed EWG Health Guidelines
Chromium
Haloacetic acids
Total trihalomethanes
Explanation:
https://www.ewg.org/tapwater/system.php?pws=SD4600356