A higher population density, faster transmission rate, and ot CD longer infectious period each cause a disease like influenza to spread to more people. Which of the following statements correctly explain why? 1. At high densities, infected individuals encountrr more individuals who are also infected. 2. At high transmission rates, an infected-susceptible encounter is more likely to result in an infection. 3. With long recovery, an infected individual is contagious longer and can infect more susceptibles.