Find the missing value for the radioactive isotope. $($Round your answer to two decimal places.$)$

$\backslash$table$[[$Isotope$,\backslash$table$[[$Half$-$life$],[($years$)]],\backslash$table$[[$Initial$],[$Quantity$]],\backslash$table$[[$Amount After$],[1000$ Years$]]],{[}^{14}C,5715,,9g$