How many milliliters of O2 gas at 25 C and 1.00 atm pressure are obtained by the thermal decomposition of 0.240 g of KMnO4?

How many milliliters of O2 gas at 25 ∘C and 1.00 atm pressure are obtained by the thermal decomposition of 0.240 g of KMnO4? The balanced equation for the reaction is 2KMnO4(s)→K2MnO4(s)+MnO2(s)+O2(g).

answer in ml