The velocity$-$time graph of a body has a negative slope. The body is undergoing

Identify what the graphs shown below indicate.

What do you understand by the displacement-time graph? Draw a displacement-time graph for a girl going to school with uniform velocity. How can we calculate the uniform velocity from it?

What is the quantity which is measured by the area occupied below the velocity-time graph?

The graph given below is the distance-time graph of an object.
$(i)$ Find the speed of the object during the first four seconds of its journey.
(ii) How long was it stationary?
(iii) Does it represent a real-life situation? Justify your answer.

Four cars $A$,$B$,$C$ and $D$ are moving on a levelled road. Their distance versus time graphs are shown in the figure. Choose the correct statement.