How many isomers of $C_4H_{11}N$ are tertiary amines?

Correct sequence of reagents for the conversion shown in the image is $-$

Identify the alkene obtained as the major product in the following Hofmann elimination reaction.
$(CH_3CH_2CH_2)N^{+}(CH_2CH_3)_3 I^{-}$ $\xrightarrow[\Delta]{\text{moist } Ag_2O} A$ $\xrightarrow[\Delta]{\text{heat}} \text{Alkene} + \text{Amine}$

Assertion : Benzene diazonium salt on boiling with water forms phenol.
Reason : $C-N$ bond is polar.

In the following reactions,the major product $W$ is

Acetic acid on heating with $NH_3$ forms $A$. When $A$ reacts with $LiAlH_4$ followed by hydrolysis,it gives $B$. When $B$ is heated with chloroform in $KOH$ medium,it gives $C$. What are $B$ and $C$ respectively?