Dr. Murdock says there are 1.9 million undocumented immigrants in Texas, and 11-12 million in the U.S. He also explains that the way demographers can make these estimates with a high degree of certainty is because the ___________ of this population cannot be hidden." "Dr. Murdock says there are 1.9 million undocumented immigrants in Texas, and 11-12 million in the U.S. He also explains that the way demographers can make these estimates with a high degree of certainty is because the ___________ of this population cannot be hidden." deaths weddings serious illnesses