1. Use the slope formula to answer Parts I, II, and III. Part I: Find the slope of the line that passes through the following points. (6 points; 2 points each) A (10, 4) and B (–2, –5) C (–7, 1) and D (7, 8) E and F Part II: Robert says that the slope of a line passing through (1, 7) and (3, 9) is equal to the ratio . Is this a correct method for calculating the slope? Explain your answer. (1 point) Part III: Do the points in the following set lie on the same line? Explain your answer. Show all work. (4 points) A (1, 3) B (4, 2) C (–2, 4)