What were zeppelins?
a. treaties made between the allied powers.
c. guns which allowed shelling from 10 miles away.
b. balloons carrying bombs.
d. poisonous gases used for a brief period of time.

i believe

clean air is essential for health and survival

clean air provides nitrogen gas for plant respiration

clean air supplies oxygen that enables living organisms to breathe

hope this

i am brianly

sorry if this doesn't

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