Answer
a. The equation of the parabola is of the form $y^2=4px$
Work Step by Step
If the equation for the parabola is of the form $y^2=px$ then the parabola will have an axis of symmetry on the x-axis. If the equation for the parabola is of the form $x^2=px$ then the parabola will have an axis of symmetry on the y-axis. The graph shown has an axis of symmetry on the x-axis, hence the equation for the parabola is of the form $y^2=4px$.