A rectangular film of liquid is extended from \((4~\text{cm} \times2 ~\text{cm})\) to \((5 ~\text{cm}\times 4 ~\text{cm})\). If the work done is \(3 \times 10^{-4}~\text{J},\) the value of the surface tension of the liquid is: 
1. \(0.25\) N/m
2. \(0.125\) N/m
3. \(0.2\) N/m
4. \(8.0\) N/m

A rectangular film of liquid is extended from \((4~\text{cm} \times 2~\text{cm})\) to \((5~\text{cm} \times 4~\text{cm}).\) If the work done is \(3\times 10^{-4}\) J, the value of the surface tension of the liquid is:
1. \(0.250\) Nm^–1
2. \(0.125\) Nm^–1
3. \(0.2\) Nm^–1
4. \(8.0\) Nm^–1