What do the slope and the area under the $v-t$ graph represent?

$A$ small electric car has a maximum constant acceleration of $1\,m/s^2$,a maximum constant deceleration of $2\,m/s^2$,and a maximum speed of $20\,m/s$. The amount of time it would take to drive this car $1\,km$ starting from rest and finishing at rest is $.........\,s$.

$A$ car starts from rest and moves with uniform acceleration $a$ on a straight road from time $t = 0$ to $t = T$. After that,a constant deceleration $a$ brings it to rest. In this process,the average speed of the car is

The position-time $(x-t)$ graphs for two children $A$ and $B$ returning from their school $O$ to their homes $P$ and $Q$ respectively are shown in the figure. Choose the correct entries in the brackets below:
$(a)$ $(A/B)$ lives closer to the school than $(B/A)$
$(b)$ $(A/B)$ starts from the school earlier than $(B/A)$
$(c)$ $(A/B)$ walks faster than $(B/A)$
$(d)$ $A$ and $B$ reach home at the (same/different) time
$(e)$ $(A/B)$ overtakes $(B/A)$ on the road (once/twice)

The speed-time graph of a particle moving along a fixed direction is shown in the figure. What is the average speed of the particle over the intervals: $(a)$ $t = 0\; s$ to $10\; s$,and $(b)$ $t = 2\; s$ to $6\; s$?

The position-time graph for a body moving along a straight line between $O$ and $A$ is shown in the figure. During its motion between $O$ and $A$,how many times does the body come to rest?