A reaction $2\mathrm{A}\to \mathrm{P}$ is second order with $k=0.0125\mathrm{L}\mathrm{mo}{\mathrm{l}}^{-1}{\mathrm{s}}^{-1}$ (for $-d[\mathrm{A}]/dt=k[\mathrm{A}{]}^2$). Calculate its half-life, in minutes (two decimals), when $[\mathrm{A}{]}_0=0.20\mathrm{mol}{\mathrm{L}}^{-1}$.

Numerical answer type, answer in min, tolerance 0.02.