Answer:
The correct answer is option D.
Explanation:
Step 1: 
Step 2: 
Overall reaction can be determined by adding all the reactions of mechanism:

Reactants in an overall reaction = 
Products in an overall reaction = 
According to question , the role of oxygen gas is product.
If H+ would have to dissociate from a substance and must be the only positive ion in the solution that substance must be an acid.
CH3CHO is an aldehyde called acetaldehyde.
CH3CH2OH is an alcohol called ethanol
CH3OCH3 is an ether called dimethyl ether.
and finally, the answer CH3COOH is a weak acid called acetic acid.
Answer:
Forests prevent desertification.
Explanation:
A displacement reaction Would occur in this situation
<span>1. Blocks Ultra violet rays that can be harmful.
2. Provides Oxygen, so we can live.
3. It blocks meteors from hitting Earth's surface.
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