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Evgen [1.6K]
3 years ago
7

The radioactive isotope 14C has a half-life of approximately 5715 years. A piece of ancient charcoal contains only 81% as much o

f the radioactive carbon as a piece of modern charcoal. How long ago was the tree burned to make the ancient charcoal
Mathematics
1 answer:
NikAS [45]3 years ago
5 0

Answer:

1758 years

Step-by-step explanation:

0.693/t1/2 = 2.303/t log No/N

t1/2 = half life of the C-14

t= time taken

No= amount of radioactive material originally present

N= amount of isotope after time t.

But N= 0.81 No

0.693/5715= 2.303/t log No/0.81No

0.00012 = 0.211/t

t =0.211 /0.00012

t= 1758 years

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A cold front changes the temperature by -3 F each day. If the temperature started at 0 F, what will the temperature be after 5 d
asambeis [7]

Answer:

The temperature falls 3 degrees avery day so you expect to drop 5 times after 5 days. So the temperature will fall by 5*3 = 15 dgrees. If we started at 0 degrees. We will have -15 degrees.

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3 years ago
The perimeter of a school gym is 522 feet. The gym measures 80 feet wide. Determine the length of the school. PLEASE EXPLAIN THE
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Total perimeter is 522 ft. I will guess the gym is a big rectangle. 

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3 years ago
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