An entomologist discovered a new insect species. The population of the insect species can be modeled by P(n) = 3,450 · bn, where n is the number of days and b is an unknown positive base. Based on the model, there were initially
insects.

If b = 1.75, the daily percent growth rate of the new insect would be
%.

If there are 55,200 new insects after 4 days, then b =
.