Question

which human activity can decrease the oxygen levels present in the atmosphere? ​

Answer 1

Answer:

cutting down of trees.

Explanation:

hope this answer helps you out

Answer 2

Answer:

cutting down of trees and burning of petroleum gases.

Explanation:

bcs if we cut trees regularly the oxygen is going to decrease slowly.

and if we use excessive petroleum then it would release harmful gases and spread in the atmosphere. which will decrease the level of oxygen.

I hope it will be helpful to you.

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