C)8% per hour
1) In this question, the key to solving this question is the factor of decay.
2) Let's rewrite it step by step so that it is clear enough to answer the question:
[tex]\begin{gathered} a=0.65\left(1-0.08\right)^t \\ a=0.65\left(0.92\right)^t \end{gathered}[/tex]As we can see, in this question there is a decay of 0.08 ( 8% per hour)
