\textbf{176.} A scientist refers to an old charcoal sample and claims that the age of this charcoal is about 22920 years. To confirm this claim, carbon-14 in this charcoal: what percentage of the normal amount of carbon-14 present in fresh charcoal must have been newly produced? (Half-life of carbon-14 is 5730 years.)
\begin{center}
(1) $1.56$ \quad (2) $3.13$ \quad (3) $6.25$ \quad (4) $12.5$
\end{center}