mg src="../images/chp04/simple-closed-curve-pos.gif" alt="Simple curve" title="Simple curve" style="width:85%;">
                            <figcaption>
                                Positively oriented.
                            </figcaption>
                        </figure>
                    
                        <figure>
                            <img src="../images/chp04/simple-closed-curve-neg.gif" alt="Non simple curve" title="Non simple curve" style="width:85%;">
                        