For a chemical reaction A → B, it was found that concentration of B is increased by 0.2 mol L^-1 in 30 min. The average rate of the reaction is \ \ \…

For a chemical reaction $\displaystyle A \rightarrow B$, it was found that concentration of $\displaystyle B$ is increased by $\displaystyle 0.2 \mathrm{~mol} \mathrm{~L}^{-1}$ in $\displaystyle 30 \mathrm{~min}$. The average rate of the reaction is \_\_\_\_ $\displaystyle \times 10^{-1} \mathrm{~mol} \mathrm{~L}^{-1} \mathrm{~h}^{-1}$. (in nearest integer)