An old car travels due south. The distance it travels at hourly intervals is shown in Table

Question:

An old car travels due south. The distance it travels at hourly intervals is shown in Table 1.5.
a. Draw a distance–time graph to represent the car’s journey.
b. From the graph, deduce the car’s speed in km h⁻¹ during the first three hours of the journey.
c. What is the car’s average speed in km h⁻¹ during the whole journey?