What does a vehicle's speedometer measure: instantaneous velocity or instantaneous speed?

The velocity $(v)$ of a particle moving along the $x$-axis varies with its position $(x)$ as shown in the figure. How does the acceleration $(a)$ of the particle vary with position $(x)$?

$A$ particle shows a distance-time curve as given in the figure. The maximum instantaneous velocity of the particle is around the point:

Find the acceleration of the particle at $x = 5\,m$ using the given $v^2-x$ graph,where $v$ is velocity and $x$ is displacement.

$A$ bird flies for $4 \, s$ with a velocity of $|t - 2| \, m/s$ in a straight line,where $t$ is time in seconds. It covers a distance of ......... $m$.

The distance covered by the particle in the last $2\,s$ is what fraction of the total distance covered by it in $7\,s$?