A basement room containing radon gas (t1/2 = 3.82days) is sealed to be airtight.
(a) If 7.50 x 1010 radon atoms are trapped in the room, estimate how many radon atoms remain in the room after one week.
(b) Radon undergoes alpha decay. After 30 days, is the number of its daughter nuclei equal to, or less than, the number of radon parents that have decayed? Explain your reasoning.