For the decomposition of azomethane. ${\mathrm{CH}}_3{\mathrm{N}}_2{\mathrm{CH}}_3\left(\mathrm{g}\right)\to {\mathrm{CH}}_3{\mathrm{CH}}_3\left(\mathrm{g}\right)+{\mathrm{N}}_2\left(\mathrm{g}\right)$ a first order reaction, the variation in partial pressure with time at 600 K is given as

The half life of the reaction is _____ × 10^–5s. [Nearest integer]