$A$ particle moves along the $x$-axis in such a way that its $x$-coordinate varies with time according to the equation $x = 4 - 2t + t^2$. The velocity of the particle will vary with time as:

From the following displacement-time graph,find the velocity of a moving body.

The velocity-time graph for a car is a semicircle as shown in the figure. Which of the following statements is correct?

The positions of two cars $A$ and $B$ are given by $X_A = at + bt^2$ and $X_B = ft - t^2$. At what time will both cars have the same velocity?

The $x-t$ graph for a uniformly accelerated particle is as shown in the figure. Find the average velocity between points $(i)$ and $(ii)$ in $ms^{-1}$.

The velocity $(v)$ versus time $(t)$ plot of a particle is shown in the figure, for a time interval of $40 \text{ s}$. The total distance travelled by the particle and the average velocity during this period are, respectively . . . . . . .