To destroy a cancerous tumor, a dose of gamma radiation with a total energy of 2.11 J is to be delivered in 29.0 days from implanted sealed capsules containing palladium-103. Assume this isotope has a half-life of 17.0 d and emits gamma rays of energy 21.0 keV, which are entirely absorbed within the tumor. (Enter your answer using one of the following formats: 1.2e-3 for 0.0012 and 1.20e+2 for 120.)
(a) Find the initial activity of the set of capsules.
(b) Find the total mass of radioactive palladium that these "seeds" should contain.