….."………….."……how do u do dis?

No solution : there is no number of boxes that she bought

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.

8,400-6,400=xx/6,400anyways the percent increase is 31.25% or 0.3125 you can round if you can