Another group of Girl Scouts shared their data for the number of boxes each girl sold in a day. The graph below shows their data. Four girls sold two boxes each, two girls sold
three boxes each and one girl sold 28 boxes.

21

step-by-step explanation:

21-4

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.