Answer: exotic medium can be engineered to slow light
Explanation:
Answer:
each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element.
"some elements have only one stable isotope"
Explanation:
there ya go! Pls give me brainliest!
The answer is C) A girl hangs by both hands, motionless, from a trapeze.
Basically it is the difference in velocity divided by the time it takes to make that change.
Answer:
200 million years
Explanation:
The equation that describes the decay of a radioactive isotope is

where
is the amount of radioactive isotope left at time t
is the initial amount of isotope
is the half-life of the sample
In this problem, the ratio between unstable isotope and daughter isotope is 1:15; this means that

Because the "total proportion" of original sample was 1+15=16.
Also we know that the half-life is

So we can re-arrange the equation to find t, the age of the rock:

So, 200 million years.