Let $\mathrm{P}\left(\mathrm{x}_1, \mathrm{y}_1\right)$ and $\mathrm{Q}\left(\mathrm{x}_2, \mathrm{y}_2\right), \mathrm{y}_1<0, \mathrm{y}_2<0$, be the end points of the latus rectum of the ellipse $\mathrm{x}^2+4 \mathrm{y}^2=4$. The equations of parabolas with latus rectum PQ are
