(a) Use a graphing utility to graph the curves represented by the two sets of parametric equations.

(b) Describe the change in the graph when the sign of the parameter is changed.
(c) Make a conjecture about the change in the graph of parametric equations when the sign of the parameter is changed.
(d) Test your conjecture with another set of parametric equations.

x = 4 cos t y = 3 sin t x = 4 cos(-t) y = 3 sin(-t)