A sample of radioactive waste has an activity of 2.4×105 Bq2.4\times10^5\ \mathrm{Bq}2.4×105 Bq and a half-life of 5 days. A stated storage procedure requires its activity to fall below 1.0×104 Bq1.0\times10^4\ \mathrm{Bq}1.0×104 Bq before the next handling stage. After which time is this condition first met?
252525 days
202020 days
303030 days
151515 days