$\frac{0}{0\mathrm{.}75}$ points

nobject begins at position $x=0$ and moves one$-$dimensionally along the $x-$axis with a velocity $v$ expressed as a function of time $t$ according to the graph above. At what time pes the object pass through $x=0$ again?

After $40$ s$.$

Between $10$ s and $20$ s $.$

Between $20$ s and $30$ s $.$

At $30$ s exactly.

Between $30$ s and $40$ s$.$