Question

Mountaineers carry ___cylinders with them.

a. Oxygen.

b.Hydrogen

c.Nitrogen

d.Carbon dioxide​

Answer 1

Answer:

from the above question answer is oxygen

Answer 2

Answer:

a. Oxygen

Step-by-step explanation:

Because of air density above certain hight levels oxygen density reduces that's why to respiration purpose they take oxygen cylinders with them.

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