What is a velocity-time graph? State how it can be used to find:
$(i)$ The acceleration of a body.
$(ii)$ The displacement of the body.
$(iii)$ The distance travelled in a given time.

(N/A) In a velocity-time graph,time is plotted along the $x$-axis and velocity is plotted along the $y$-axis.
$(i)$ Since acceleration $=$ Change in velocity $/$ Time,the slope of the velocity-time graph gives the acceleration. If the slope is positive,it represents accelerated motion; if the slope is negative,it represents retarded motion.
$(ii)$ Since velocity $\times$ time $=$ displacement,the area enclosed between the graph and the time axis represents the displacement. The area above the time axis is considered positive displacement,and the area below the time axis is considered negative displacement. The total displacement is the algebraic sum of these areas.
$(iii)$ The total distance travelled by the body is the arithmetic sum of the magnitudes of the areas enclosed by the velocity-time graph and the time axis (ignoring the sign).