(Direct numerical prediction of activity)
A hospital receives a shipment of an isotope X whose half-life is 8 days. At the moment it leaves the supplier the activity of the shipment is 5.0 MBq.
(i) Calculate the activity of the shipment when it reaches the hospital 24 days later.
(ii) Determine the time required (from the moment it leaves the supplier) for the activity to fall to 0.625 MBq.