Williamson synthesis of ether is an example of

Which of the following ethers is gaseous at room temperature?

Write equations of the following reactions:
$(i)$ Friedel-Crafts reaction - alkylation of anisole.
$(ii)$ Nitration of anisole.
$(iii)$ Bromination of anisole in ethanoic acid medium.
$(iv)$ Friedel-Craft's acetylation of anisole.

Why is the $C-O-H$ bond angle in alcohol slightly less than the tetrahedral angle,whereas the $C-O-C$ bond angle in ether is slightly greater?

What is $X$ in the following reaction?

Consider the following reaction.
$C_6H_5-O-CH_2-C_6H_5 + HI \rightarrow \text{Product}$
Statement $I$ : In the above reaction, the product formed will be a mixture of benzyl alcohol and iodobenzene.
Statement $II$ : In the above reaction, the $-O-CH_2-$ bond is cleaved to give the product.
In the light of the above statements, choose the correct answer from the options given below: