Question 29 1 pts The figure below shows displacement-time graphs for two identical oscillators. What is the estimated phase difference between the two oscillations? 100 0.73 0.25 Displacement in ce -0.25- -0.75 -1 00 Time in ma O About 68 degrees. O Around 90 degrees. O Around 180 degrees. O Around 108 degrees. Around 40 degrees. Question 30 1 The figure below shows the trace on an oscilloscope screen when sound waves are detected by a microphone. The time-base is set at 2 ms per division . Determine the frequency of the sound waves. Give your answer to O decimal places