Answer:
Iran
Step-by-step explanation:
They are essentially asking us to solve:

Solving this equation for x tells us that it will take around 80.1 years for the materials in the vault to reduce to 357 pounds.
None of them make it an integer because none make it a whole number
Proved
Step-by-step explanation:
Cosec2A + cot2A = cotA
On Left hand-side



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Trigonometric ratios: brainly.com/question/12462203
Keywords: Trigonometeric
#LearnwithBrainly
Answer:
I draw cylinders with circles and lines