The diagram below shows the displacement against time graph for a wave on a rope. Displacement a) State the phase difference between points A and B. b) State the phase diffelrence between points A and D. c.) State the phase different between points C and D. 9. A displacement time graph for two waves A and B of the same frequency are shown below. Displacement A O 2 3 5 6 8 9 10 Time (ms) a) What is the period and the frequency of the waves based on the graph above? b) Calculate the phase difference between waves A and B in degrees