Answer and explanation:
To find the slope between points A and B, divide the change in y by the change in x. The change in y = 6 and the change in x = 9: 6 ÷ 9 = 2/3
To find the slope between points B and C, divide the change in y by the change in x. The change in y = 10 and the change in x = 15: 10 ÷ 15 = 10/15 = 2/3
The slope of the line between any two points on the graph is 2/3 because it is a straight line
Hope this helps!
The picture is for part a