Units And Measurement And Dimensions

A physical quantity $S$ is related to four observables $a, b, c$ and $d$ as $S=\frac{\sqrt{a b}}{c^3 d^4}$. If the percentage errors of measurement in $a, b, c$ and $d$ are $2 \%, 1 \%, 1 \%$ and $1 \%$ respectively, then percentage error in the quantity $S$ is