$S = \frac FL$ $\Rightarrow[ T ]=\left[ MT ^{-2}\right]$

$[ E ]=\left[ ML ^2 T ^{-2}\right]$

${[ V ]=\left[ LT ^{-1}\right] }$

${[ T ]=[ T ] }$

${\left[ MT { }^{-2}\right]=\left[ E ^{ x } V ^{ y } t ^{ z }\right]=\left[ ML ^2 T ^{-2}\right]^{ x }\left[ LT ^{-1}\right]^{ y }[ T ]^{ z } }$

Comparing coefficients

$x=1$

$2 x+y=0$

$-2 x-y+z=-2$

Solving above equations $x =1, y =-2, z =-2$

Substituting in expression of surface tension:

$S = EV ^{-2} T ^{-2}$