A population of animals has a per-capita birth rate of b = 0.17 per year and a per-capita death rate of m 0.1 per year. The population density. P(t) is found to satisfy the differential equation dP(t) dt bP(t)-mP(t). (a) If the population is initially P(0)=900, find how big the population will be in 6 years. Population= (b) When will the population double? Doubling time= years