ANSWER

EXPLANATION
Since the parabola has the (0, 0) and the directrix at y=2.
The equation is of the form

where (h,k) is the vertex.
The vertex is half way between the directrix and the focus.
The vertex will be at (0,1)
and is the distance from the vertex to the focus which is 1.


13.5 is your answer, here u are
Yes, that is true, you have to simplify -42/-45 to be able to see if they are equivalant.
It is systematic because they are going every tenth person