Answer:
This is a radioactive decay / half-life problem.
Initial amount of C 14 = 100% Present Amount = 57%
k = .0001 (that value should be negative)
Nt = No * e^ (k*t)
You need to solve that equation for "time" (equation attached)
time = natural log (Ending amount / Starting Amount) / k
time = natural log (57% / 100%) / -.0001
time = ln (.57) / -.0001
time = -.56211891815 / -.0001
time = 5,621.2 years (age of the bird skeleton)
These problems are quite complicated but I think I know this pretty well.
Need to know more? Visit my website (it's on the graphic).
Step-by-step explanation:
Answer:
3.4
Step-by-step explanation:
Standard deviation of a population is defined as:
σ² = ∑(xᵢ − μ)² / n
The standard deviation of a sample is defined as:
s² = ∑(xᵢ − x)² / (n - 1)
It's not clear which one we have, so let's calculate both.
First, we must find the mean.
μ = (5+12+15+10+12+6+8+8) / 8
μ = 9.5
Now we find the squares of the differences:
(5-9.5)² + (12-9.5)² + (15-9.5)² + (10-9.5)² + (12-9.5)² + (6-9.5)² + (8-9.5)² + (8-9.5)²
= 80
Divide by n:
σ² = 80 / 8
σ² = 10
And take the square root:
σ = √10
σ ≈ 3.2
That's not one of the answers, so let's try the standard deviation of a sample instead of a population.
Instead of dividing by n, we'll divide by n-1:
s² = 80 / 7
And take the square root:
s = √(80/7)
s ≈ 3.4
So that must be it.
The answer is 18
-7^2+4(-7)-3
49+(-28)-3
21-3
18
6(2(5) - 4)
6(10 - 4)
6(6)
36
Answer:
16 and 82 degrees
Step-by-step explanation:
You can sum all of the angles together and solve for x.
(x - 1) + (5x - 3) + (5x - 3) = 180
11x - 7 = 180
11x = 187
x = 17
The first angle is 16 degrees. (17 - 1)
The other two angles are 82 degrees(5(17) - 3)
