In the laboratory, $H_2O_2$ is prepared by:

The strength of $50$ volume solution of hydrogen peroxide is $...... \ g/L$ (Nearest integer). Given: Molar mass of $H_2O_2$ is $34 \ g \ mol^{-1}$. Molar volume of gas at $STP = 22.7 \ L$.

$H_2O_2$ reacts as a reducing agent with:
$(I)$ $KMnO_4$
$(II)$ $K_2Cr_2O_7$
$(III)$ $Ag_2O$
$(IV)$ $HNO_3$

$H_2O_2$ is always stored in black bottles because

Hydrogen peroxide is used as

Which one of the following gives the highest volume of $O_2$ at $STP$ on complete decomposition?