8. Can the digital waveform in Figure 1-61 be called a pulse train? 9. What is the frequency of the waveform in Figure 1-61? 10. Is the pulse waveform in Figure 1-61 periodic or nonperiodic? 11. Determine the duty cycle of the waveform in Figure 1-61. rims) 3 5 7 9 11 13 15 17