Consider the following deterministic \"two-level\" testing scheme. We divide a population of n individuals to he tested into C arhitrarv groups of the same size. We then test each of these groups in aggregate. For an}r group that comes back positive, we retest all members of the group individually. Show that there is a choice for C such that, if 1: individuals in the population have COVIDlg, we can nd all of those individuals with 5 21.3711: tests. You can assume it is knot-m in advance {often it can be estimated accurater from the positive rate of prior tests). This is already an improvement on the naive 11. tests when it t: 25% - n