Answer:
The coefficient is 0.90
Explanation:
Drawing a diagram makes thing easier, we will assume that the acceleration tends to zero because it start barely moving.
Is there more info or is that just the question
The symbol c represents the speed of light.
Until there's none of it left. Different radioactive isotopes decay at different rates. And a bigger pile of it will last longer than a smaller pile. Without knowing WHICH radioactive isotope you're asking about, and how much of it you started out with, the answer could turn out to be anywhere between 1 millionth of a second and 1 million years.