4. Sketch and describe a first harmonic. 5. Sketch and describe a second harmonic. 6. Sketch and describe a third harmonic. 7. If a string is 1.6 meters long and it vibrates in the first and second harmonics, determine the wavelength for each pattern. 8. A string (xed on both ends) is 2.4 meters long and is vibrating as the first harmonic. The string vibrates up and down with 30 complete vibrational cycles in 5 seconds. Determine the frequency, period, wavelength, and speed for this wave