A unimolecular, irreversible liquid-phase reaction
$$\boldsymbol{A} \longrightarrow \boldsymbol{P}$$
was carried out in an ideal batch reactor at temperature $T$. The rate of the reaction $\left(-r_A\right)$ measured at different conversions $X_A$ is given in the table below. This reaction is also carried out in an ideal continuous stirred tank reactor $\text{(CSTR)}$ at the same temperature $T$ with a feed concentration of $1 \mathrm{~mol} . \mathrm{m}^{-3}$, under steady-state conditions. For a conversion of $0.8,$ the space time $\text{(in s)}$ of the $\text{CSTR}$ is_______________(in integer).
$$\begin{array}{|c|l|l|l|l|l|l|}
\hline X_A & 0 & 0.1 & 0.2 & 0.4 & 0.6 & 0.8 \\
\hline-r_A\left(\mathrm{~mol} . \mathrm{m}^{-3} \mathrm{~s}^{-1}\right) & 0.45 & 0.35 & 0.31 & 0.18 & 0.11 & 0.05 \\
\hline
\end{array}$$