300 female osprey hatch-lings were tracked until they died or succeeded in laying their own eggs. Based on data, the researchers concluded that somewhere between 12% and 18% of all female osprey hatch-lings in the US succeed in growing up to lay their own eggs

Period is the time it takes for one “cycle” to complete. in the parent sine function, period is 2*pi since sin(0) = 0, sin(pi/2) = 1, sin(pi) = 0, sin(3pi/2) = -1, and sin(2pi) = 0. at that point, the sequence repeats itself. i’m not sure if your graph is similar to the sine function since you didn’t provide a picture, but you can find the period by looking at a graph.