What is the relationship between the distance travelled and the time elapsed for motion with uniform velocity ?

The velocity-time graph of cars $A$ and $B$ which start from the same place and move along a straight road in the same direction is shown below

Calculate :

$(a)$ the acceleration of car $B$ between $2 \,s$ and $4\, s$.

$(b)$ the time at which both the cars have the same velocity.

$(c)$ the distance travelled by the two cars $A$ and $B$ in $8\, s$

$(d)$ Which of the two cars is ahead after $8\, s$ and by how much ?

A body is moving along a circular path of radius $R$. Find the displacement of the body when it completes half a revolution.

State the meaning of uniform circular motion.

Study the speed$-$time graph of a car below and answer the following questions

$(a)$ What type of motion is represented by $OA$ ?

$(b)$ Find acceleration from $B$ to $C$.

$(c)$ Calculate the distance covered by the body from $A$ to $B$.