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Anna35 [415]
2 years ago
12

Carbon-14 dating assumes that the carbon dioxide on Earth today has the same radioactive content as it did centuries ago. If thi

s is true, the amount of 14C absorbed by a tree that grew several centuries ago should be the same as the amount of 14C absorbed by a tree growing today. A piece of ancient charcoal contains only 38% as much of the radioactive carbon as a piece of modern charcoal. How long ago was the tree burned to make the ancient charcoal? (The half-life of 14C is 5715 years. Round to the nearest year.)
Mathematics
1 answer:
defon2 years ago
7 0

7978 years

Step-by-step explanation:

A = A02^(-t/hl)

where hl = half-life.

Dividing both sides by A0 and taking the logarithm, we get

ln(A/A0) = -(t/hl)ln2

or solving for t,

t= -(hl)ln(A/A0)/ln2

note that A/A0 = 0.38

t = -(5715 yrs)[ln(0.38)/ln2]

= 7978 years

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<h3>To find the product of 42.12 and 10^3,  move the decimal point in 42.12 3 places to the right because 10^3 has 3 zeros</h3>

<em><u>Solution:</u></em>

Given that,

\text{ product of } 42.12 \text{ and } 10^3

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3 years ago
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Answer:

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Step-by-step explanation:

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