A population starts at size 20, and has a 6 year cycle: gain 1, lose 2, gain 3, lose 4, gain 3, lose 2.
In each of the above population, immigration changes over time according to a fixed pattern (rather than a random pattern). For each population, find the population in each of the first 6 years and sketch a graph. Do you think it will grow or shrink in the long run? Find the average immigration in each case. Does an average greater than 0 mean that the population is growing?