What would be the growth rate ( r ) of an island population of 1,000 that has 30 births per 100 population, 20 death per 100 population, 5 immigrants per 100 population, and 10 emigrants per 100 population?

A) +5
B) − 50
C) +50
D) − 150
E) +150

The growth rate (r) is calculated by subtracting the death rate and emigration rate from the birth rate and immigration rate. Here, (30 births + 5 immigrants) - (20 deaths + 10 emigrants) = 35 - 30 = +5 per 100 population. For a population of 1,000, this translates to a growth rate of +50.