The tension in a stretched string fixed at both ends is changed by 2% , the fundamental frequency is found to get changed by 15 Hz. Select the correct statement(s).

Wavelength depends on length which is fixed. Therefore wavelength does not change.

So the velocity $\mathrm{\nu }=\sqrt{\frac{\mathrm{T}}{\mathrm{\mu }}}\Rightarrow \mathrm{\nu }\propto \sqrt{\mathrm{T}}$

So, Percentage change in velocity = $\frac{1}{2}\times$ Percentage change in tension. 

2% change in tension will cause a 1% change in velocity.

velocity= wavelength x frequency.

Percentage change in velocity =  Percentage change in tension.

So the 15 Hz change in frequency accounts for 1% of change. 

The original frequency = 1500 Hz.