If $y$-coordinate of a point is zero, then this point always lies

If the coordinates of two points are $\mathrm{P}\left(-2, 3\right)$ and $\mathrm{Q}\left(-3, 5\right)$, then (abscissa of $\mathrm{P}$) $-$(abscissa of $\mathrm{Q}$) is

If $\mathrm{P}\left(5, 1\right), \mathrm{Q}\left(8, 0\right), \mathrm{R}\left(0, 4\right), \mathrm{S}\left(0, 5\right)$ and $\mathrm{O}\left(0, 0\right)$ are plotted on the graph paper, then the point(s) on the$x$-axis are

The point whose abscissa and ordinate have different signs will lie in