Which of the following velocity-time graphs shows a realistic situation for a body in motion?

Refer to the graph in figure. Match the following:

Graph	Characteristics
$(A)$	$(i)$ has $v > 0$ and $a < 0$ throughout
$(B)$	$(ii)$ has $x > 0$ throughout and has a point with $v = 0$ and a point with $a = 0$
$(C)$	$(iii)$ has a point with zero displacement for $t > 0$
$(D)$	$(iv)$ has $v < 0$ and $a > 0$

The given graph shows the variation of velocity with displacement. Which one of the graphs given below correctly represents the variation of acceleration with displacement?

Among the four graphs shown in the figure,there is only one graph for which the average velocity over the time interval $(0, T)$ can vanish for a suitably chosen $T$. Which one is it?

The $v-t$ graph of a rectilinear motion is shown in the adjoining figure. The distance from the starting point after $8 \text{ s}$ is .......... $\text{m}$.

Between two stations,a train accelerates uniformly at first,then moves with constant velocity,and finally retards uniformly. If the ratio of the time taken is $1 : 8 : 1$ and the maximum speed attained is $60\,km/h,$ what is the average speed over the whole journey in $km/h$?