Horizontal Parabola Focus and Directrix Exploration

How is a horizontal parabola different from a vertical one? How are they the same?

Which parameter - a, h, or k - changes the distance of the focus and the directrix from the parabola?

What happens to the focus and the directrix as "a" gets further away from 0? What happens to them as "a" gets closer to 0?

How do "h" and "k" change the focus and the directrix?

What does "c" represent on the graph of a parabola? Be sure to change the values of "h" and "k" to make sure you're correct?