What can you say about the motion of a body whose distance-time graph is a straight line parallel to the time axis?

7 A car increases its speed from 20km/h to 50km/h in 10 seconds. Find its acceleration. 8 Name the two quantities, the slope of whose graph gives
(i) Speed
(ii) Acceleration. 10 Define average speed with example. 11 Differentiate between displacement and distance.