Answer:

Step-by-step explanation:
If we have an initial amount of a radioactive material or substance, which is
, and we also are told this amount decays
each year, this means each year
of the substance remains:

To understand it better:
Year 1:

Year 2:

Year 3:

and so on until year
:
Year t:

Therefore, the function tha best describes this radiation decay situation is:
