Which of the following is not a vector ?

$(a)$ Derive graphically the equation for velocity$-$time relation.

$(b)$ Name the device used to measure distance travelled by a vehicle.

$(c)$ Can displacement of a moving object be zero ? Give reason.

State which of the following situations are possible and give an example of each of these

$(a)$ A body moving with constant acceleration but with zero velocity.

$(b)$ A body moving horizontally with an acceleration in vertical direction.

$(c)$ A body moving with a constant velocity in an accelerated motion.

A car travels $100\, km$ east and then $100 \,km$ south. Finally, it comes back to the starting point by the south-east route. Throughout the journey the speed is constant at $60\, km h ^{-1}$. The average velocity for the whole journey if time taken is $3.3$ hours is

Give one example for each of the type of motion when

$(i)$ acceleration is in the direction of motion.

$(ii)$ acceleration is against the direction of motion.

$(iii)$ acceleration is uniform.

Area under a $v -t$ graph represents a physical quantity which has the unit