Hello,i am having trouble answering the question C and D of this problem:

Knowing the importance of the wave velocity in determining the frequency of the modes, and that this velocity depends on the tension and linear mass density of the string, we measure the mass of the string as (2.0 0.2) g and its total length as (1.85 0.01) m. The segment of the string between the vibrator and the pulley has a length ? of (0.985 0.002) m (see Figure 2) and the rest hangs on the other side of the pulley and holds the platform with the masses.

Question C : A tensioned rope with a vibrator (identical to Figure 2 in the details of the experiment) with a linear density rope of mass 1.60 g/m is set up. A mass of 0.38 kg is suspended to create the tension in the string. Calculate the velocity (in m/s) of any wave in the string. Round it off to 2 decimal places. Question D : A stretched string with a vibrator (identical to Figure 2 in the details of the experiment) is set up where the length of the vibrating string segment is 94.0 cm. When the string vibrates at a frequency of 190 Hz, a standing wave with 8 individual segments appears. Calculate the velocity (in m/s) of the waves in this string. Round to 2 decimal places.

Question D : A stretched string with a vibrator (identical to Figure 2 in the details of the experiment) is set up where the length of the vibrating string segment is 94.0 cm. When the string vibrates at a frequency of 190 Hz, a standing wave with 8 individual segments appears. Calculate the velocity (in m/s) of the waves in this string. Round to 2 decimal places.

L Poulie Corde Vibreur Masse suspendue Fig. 2 - Installation for inducing vibrations in a string under tension.Table 2 - Frequency of vibration modes in a stretched string Suspend Number of mass the mode Frequency m (g) + 0.5 g f ( s' ) + 0.5 s 2 37.2 W 57.6 151.2 4 76.4 96.1 49.4 74.2 251.0 4 98.8 123.6 58.8 87.3 351.4 4 116.6 5 144.8