Product $A$ is

Identify the major product formed from the sequence of reactions given below:
$C_6H_5NH_2$ $\xrightarrow[(ii) Cu_2Cl_2]{(i) NaNO_2/HCl, 273 K}$ $\xrightarrow{(iii) Na/dry ether} \text{Product}$

The reactions which cannot be applied to prepare an alkene by elimination are: Choose the correct answer from the options given below $:$
$A.$ $2$-bromomethylcyclohexane + $NaOEt$
$B.$ $2$-bromobutane + $KOH$ (aq.)
$C.$ $2$-bromo-$2$-methylpropane + $NaOMe$
$D.$ Phenol + $Na_2Cr_2O_7 / H_2SO_4$
$E.$ $2$-methylpropan-$2$-ol + $Cu$ at $573 \ K$

What is the major product obtained in the following reaction?

$A$ (organic compound) $+ O_2 \to X + Y + Z$. Compound $(A)$ in pure form does not give a precipitate with $AgNO_3$ solution. $A$ mixture containing $70\%$ of $(A)$ and $30\%$ of ether is used as an anaesthetic. Compound $(X)$ and $(Y)$ are oxides while $(Z)$ is a pungent smelling gas. $(X)$ is a neutral oxide which turns cobalt chloride paper pink. Compound $(Y)$ turns lime water milky and produces an acidic solution with water. Compounds $(A), (X), (Y)$ and $(Z)$ respectively will be:

The correct order of increasing reactivity of $C-X$ bond towards nucleophile in the following compounds is:
$I$: Chlorobenzene (or aryl halide)
$II$: $2,4$-Dinitrochlorobenzene
$III$: $(CH_3)_3C-X$ ($3^o$ alkyl halide)
$IV$: $(CH_3)_2CH-X$ ($2^o$ alkyl halide)