Find points on the curve $\large\frac{x^2}{9} + \frac{y^2}{16} = 1$ at which the tangents are $(i)\; parallel\; to\; x - axis$

Question

$\begin{array}{1 1} (0,4) ; (0,-4) \\ (0,3 ) ; (0,-3) \\ (0,2); (0,-2) \\ (0,1);(0,-1) \end{array}$