Consider the family of curves $$\begin{aligned} &x=\left(2+\frac{1}{2} \sin a t\right) \cos \left(t+\frac{\sin b t}{c}\right).\\ &y=\left(2+\frac{1}{2} \sin a t\right) \sin \left(t+\frac{\sin b t}{c}\right) \end{aligned}.$$
Plot the curve for the given values of $a, b,$ and $c$ with $0 \leq t \leq 2 \pi$ (Source: Mathematica in Action, Stan Wagon, Springer, 2010 ; created by Norton Starr, Amherst College).
$$a=b=5, c=2$$