Carbon-14 has a half-life of 5,730 years. Suppose a fossil from a mammal contains one-fourth of its original amount of carbon-14. How old is the sample?

a:22,920 years
b:17,190 years
C:2,865 years
d:11,460 years

 B:17,190 years

Explanation: After 5730 years ( first half life) 70 /2 = 35 mg decays and 35 g remains left. After another 5730 years ( two half lives or 11460 years) 35 /2 = 17.5mg decays and 17.5 g remains left . After another 5730 years ( three half lives or 17190 years) 17.5 /2 = 8.75mg decays and 8.75g remains left.

i know this is off topic but, can you go to my quetions, to see if you can answer any?(or if you know anyone who can answer them)

cell regulation is conducted by special proteins.

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