Neil Armstrong stepped on the moon on the date of July 20 1969
Do you mean like, when is it good to learn about puberty, dieting, etc?
Answer: Oxygen
Explanation:
The gas that is useful for burning from the options given is oxygen. For combustion to take place, it should be noted that oxygen is required.
Fire is simply a chemical reaction that is being created from fuel and oxygen which eventually creates the heat and the light that's gotten. The percentage of oxygen that is in the air is about 21%.
The answer is C.The chinese hero yu is said to have saved china by draining the land after a huge flood. this answer shows that this person was only human but saved something still.
hope it helps!
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