Which of the following is a true structure of $H_2O_2$?

$A$ colourless liquid $A$ contains $H$ and $O$ elements only. It decomposes slowly on exposure to light. It is stabilised by mixing urea to store in the presence of light.
$(i)$ Suggest the possible structure of $A$.
$(ii)$ Write the chemical equation for its decomposition reaction in light.

Which of the following can be used to prevent the decomposition of $H_{2}O_{2}$?

Why can dilute solutions of hydrogen peroxide not be concentrated by heating? How can a concentrated solution of hydrogen peroxide be obtained?

What is the $\%$ strength of $22.4$ volume of $H_2O_2$ solution (in $\%$)?

What is the concentration of $20$ volume $H_2O_2$ in $g/L$?