A medical radioisotope sample of iodine-131 is prepared for a diagnostic scan.
At the time of preparation, the activity of the sample is 80 kBq80\text{ kBq}80 kBq.
After 6.0 days6.0\text{ days}6.0 days, the activity of the sample has decayed to 45 kBq45\text{ kBq}45 kBq.
What will the activity of the sample be, to the nearest whole number, 9.0 days9.0\text{ days}9.0 days after preparation?
24 kBq24\text{ kBq}24 kBq
30 kBq30\text{ kBq}30 kBq
34 kBq34\text{ kBq}34 kBq
38 kBq38\text{ kBq}38 kBq
