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`