The half-life of `Tc^(99)` is 6.0 hr. The delivery of a sample of `Tc^(99)` from the reactor to the nuclear medicine lab of a certain hospital takes 3.0 hr. What is the minimum amount of `Tc^(99)` that must be shipped in order for the lab to receive 10.0 mg?
A. 20.0 mg
B. 15.0 mg
C. 14.1 mg
D. 12.5 mg