In the picture below, determine the approximate quadratic function needed to fit the arches.

1. Use the sliders to fit the parabola on the arches.[br]2. What significance does the variables a, b and c have on the quadratic equation?[br]3. What do you observe of the value of the y coordinate in the roots of the equation?[br]4. What happens to the parabola as the sign of the coefficient of 'a' shifts from positive to negative?