[Kangaroo Grey 2013 Q4] There are five families living in my road. Which of the
following could not be the mean number of children per family that live there?
A 0.2
B 1.2
C 2.2
D 2.4
E 2.5

E, as this is the average per family. To get the total number of children, times the number by 5 families. With the others, you get a whole number. With E, you get 12.5 children in total which is impossible given you can’t have half children

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.