31-28 The lethal dose of radiation for mammals and birds is under 1000 rads, while it takes about 100,000 rads to kill amoebas and over 1 million rads to kill viruses. What is the likely reason for this? 31-29 Suppose 100,000 radiation workers each receive 5 rems. Is this more or less important genetically than the entire world population of about 5 billion people receiving 5 millirems? Why