Hi there!
Your answer is D. Bolivia
Hope This Helps!
Explanation:
Given the importance of oxygen for animals, researchers suspected that a sudden increase in the gas to near-modern levels in the ocean could have spurred the Cambrian explosion. ... This supported the idea of oxygen as a key trigger for the evolutionary explosion.

(simplify the equation)

(subrtact both sides by 14)


(multiply both sides by 6)

Hope it helped,
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Because we wont have water to drink or swim in or not be able to take a shower