A disease has hit a city. The percentage of the population infected t days after the disease arrives is approximated by p(t) = 7t!\" 15 for 0 s t 530. (a) After how many days is the percentage of infected people a maximum? (b) What is the maximum percent of the population infected? (a) The percentage of infected people reaches a maximum after [:I days. (Simplify your answer.) (b) The maximum percent of the population infected is 1:]%. (Round to the nearest hundredth as needed.)