Answer:
4
Step-by-step explanation:
The answer is A
Reasoning;
<span>a1 = first term;
an</span><span>= </span>a<span>n-1</span><span> + </span><span>d
</span>In a sequence you add the first term (a1) with the second term in a repeating linear equation. In this one you need to add 4 to each term so, the equation is;
a1 = 2
an = an -1 + 4
creating:
2 6 10 14 18 22 26...
No me pagan el otro porque me voy bye a mi sister o a la otra semana si pero ya me lo voy hacer y no tengo nada de nada que me pase el día y no tengo que hacer el trabajo de mi
Answer:
A) 277 million years
Step-by-step explanation:
Here, decay of U-238 is first order reaction. (since most of the nuclear decays are first order).
so, the equation t =
× ln(
)
where, t = time from start of reaction
k = reaction constant
A(0) = initial concentration; A = present concentration.
⇒ 4.5 billion = 4500 million years =
× ln2.
Now, given 95.82% of parent U-238 isotope is left.
⇒ t =
× ln(
)
t =
× ln(
)
⇒ t ≅ 277 million years.