The variation of velocity of a particle moving along a straight line with time is illustrated in the following figure. The distance travelled by the particle in $4 \, s$ is: (in $, m$)

$A$ bird flies with a velocity $(t-2) \text{ m/s}$ along a straight line, where $t$ is the time in seconds. The distance covered by it in a time of $4 \text{ s}$ is: (in $\text{ m}$)

Fill in the blanks:
$(a)$ The path length is always ............ .
$(b)$ The slope of the velocity-time graph for an object moving with acceleration is ............ .
$(c)$ If the velocity-time graph is parallel to the time-axis,the object is ............ .

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.

$A$ lift is going up. The variation in the velocity of the lift is given in the graph. What is the height to which the lift takes the passengers? (in $m$)

The displacement-time graph for two particles $A$ and $B$ are straight lines inclined at angles of $30^\circ$ and $60^\circ$ with the time axis. The ratio of velocities $V_A:V_B$ is