If $Z = {{{A^2}{B^3}} \over {{C^4}}}$, then the relative error in Z will be :
${{\Delta A} \over A} + {{\Delta B} \over B} + {{\Delta C} \over C}$
${{2\Delta A} \over A} + {{3\Delta B} \over B} - {{4\Delta C} \over C}$
${{2\Delta A} \over A} + {{3\Delta B} \over B} + {{4\Delta C} \over C}$
${{\Delta A} \over A} + {{\Delta B} \over B} - {{\Delta C} \over C}$
