For the experimental data obtained as given below for chemical rate constant, determine the value of temperature characteristic coefficient, $.$

$\backslash$table$[[$Temp $(C)$:$,10,15,20,25,30],[$ day $($:${?}^{-1}\},0\mathrm{.}40,7\mathrm{.}8,1\mathrm{.}40,2\mathrm{.}70,5\mathrm{.}50]]$