Answer:
Option D
2 m/s
Step-by-step explanation:
The speed is given by distance/time
The complete wave has a distance of 8 m (This is the wavelength)
Time taken for complete wave is 4 s
Therefore, velocity= 8 m/ 4 s= 2 m/s
The amplitude is the distance between crest and trough hence 9 m- 6 m= 3 m
Frequency is 1/period and in this case period is 4 s hence frequency= 1/4= 0.25 Hz
Essentially, what we wanted is velocity