[填空题]
A cancer patient is undergoing radiation th66e9j6 ( sj88 (,rmdsj;zdf jtipm hnaym0 ci4 /.elpherapy in which protons with an energy of 1.2 MeV are incident on a 0.25-kg tumop m./i04al cyer.
(a) If the patient receives an effective dose of 1.0 rem, what is the absorbed dose?
(b) How many protons are absorbed by the tumor? Assume $QF = 1$. $ \times 10^{10}\ \text{p}$