A parabola has a vertex at the origin. The equation of the directrix of the parabola is y is equal to 3 What are the coordinates of its focus?
A
open paren 0 comma negative 3 close parenB
open paren 0 comma 3 close parenC
open paren 3 comma 0 close parenD
open paren negative 3 comma 0 close paren