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.
Answer:
I think you should try the method of substitution???
Answer:
E.) 5 cm
Step-by-step explanation:
The shapes are congruent and are the same size, side <u>TU </u> is the same as <u>NP</u>. If <u>TU </u>is 5, then <u>NP </u>is 5.
Answer:
6
Step-by-step explanation:
Any circle in the form

Where r^2 is the radius squared, so


Answer:
kurt
Step-by-step explanation: