Answer:
The person has been dead for approximately 15,300 years
Explanation:
<u>Available data</u>:
- The half-life of carbon 14 is 5,600 years
- The human skeleton level of carbon 14 is 15% that of a living human
To answer this question we can make use of the following equation
Ln (C14T₁/C14 T₀) = - λ T₁
Where,
- C14 T₀ ⇒ Amount of carbon in a living body at time 0 = 100%
- C14T₁ ⇒ Amount of carbon in the dead body at time 1 = 15%
- λ ⇒ radioactive decay constant = (Ln2)/T₀,₅
- T₀,₅ ⇒ The half-life of carbon 14 = 5600 years
- T₀ = 0
- T₁ = ???
Let us first calculate the radioactive decay constant.
λ = (Ln2)/T₀,₅
λ = 0.693/5600
λ = 0.000123
Now, let us calculate the first term in the equation
Ln (C14T₁/C14 T₀) = Ln (15%/100%) = Ln 0.15 = - 1.89
Finally, let us replace the terms, clear the equation, and calculate the value of T₁.
Ln (C14T₁/C14 T₀) = - λ T₁
- 1.89 = - 0.000123 x T₁
T₁ = - 1.89 / - 0.000123
T₁ = 15,365 years
The person has been dead for approximately 15,300 years
Answer:
Even after an infection is over, your immune system continues to make antibodies. Once you test positive for the bacteria, your blood will continue to test positive for months or years even after the bacteria are no longer present.
Explanation:
using brain
Answer:
The answer is A.
Explanation:
Plant blindness refers to "the inability to see or notice the plants in one's own environment." The term plant blindness was coined twenty years ago by Elizabeth Schussler and James Wandersee who are botanists. Plant blindness results in "the inability to recognize the importance of plants in the biosphere and in human affairs." It is also the reason why people have a tendency of ranking “plants as inferior to animals”. Therefore, plants tend to receive limited care and upkeep. It is important to recognize plant blindness so that more intentional care can be given to preserving our plant species and ensure their survival and ability to thrive.
"Anterior" means "to the front". A horse's head is anterior to the rest of its body. Contrariwise, "posterior" means "to the back", like a horse's tail.
Hope that helped! =)
C I think, I mean it’s the only logical answer, hope this helps!
