What is the role of glycerol in the decomposition of $H_2O_2$?

Given below are two statements: One is labelled as Assertion $A$ and the other is labelled as Reason $R.$
Assertion $A:$ The dihedral angle in $H_{2}O_{2}$ in the gaseous phase is $90.2^{\circ}$ and in the solid phase is $111.5^{\circ}$.
Reason $R:$ The change in dihedral angle in the solid and gaseous phases is due to the difference in the intermolecular forces.
Choose the most appropriate answer from the options given below for $A$ and $R$.

Which one of the following reactions does not form a gaseous product?

Predict the correct product when $Cl_2$ is passed through a $H^{18}O-^{18}OH$ solution.

The correct statements from the following are:
$i$. $Ca(OH)_2$ is used in Clark's method of removal of temporary hardness of water.
$ii$. $100 \ mL$ of $10$ vol $H_2O_2$ on complete decomposition liberates $1 \ L$ of oxygen at $STP$.
$iii$. Urea can be added to the solution of $H_2O_2$ as stabilizer.

In which of the following reactions does $H_2O_2$ act as a reducing agent?