The order of stability of the following tautomeric compounds is:
$(I) CH_2=C(OH)-CH_2-C(=O)-CH_3$
$(II) CH_3-C(=O)-CH_2-C(=O)-CH_3$
$(III) CH_3-C(OH)=CH-C(=O)-CH_3$

Identify the pairs of compounds that represent chain isomerism among the following:
$I. CH_3-CH_2-CH_2-CH_2-OH$ (Butan$-1-$ol)
$II. CH_3-CH_2-CH(OH)-CH_3$ (Butan$-2-$ol)
$III. (CH_3)_3C-OH$ ($2$-Methylpropan$-2-$ol)
$IV. (CH_3)_2CH-CH_2-OH$ ($2$-Methylpropan$-1-$ol)

The two compounds given below are:

$Nitroethane$ can exhibit one of the following kinds of isomerism:

Identify the isomerism exhibited by methoxyethane and propan-$1$-ol.

Identify the correct statements from the following. Choose the correct answer from the options given below.
$A$. Pentan$-3-$one and Pentan$-2-$one are metamers.
$B$. Butanenitrile and Butaneisonitrile are functional isomers.
$C$. Butan$-1-$ol and Butan$-2-$ol are position isomers.
$D$. Butan$-1-$amine and $N$-methylpropan$-1-$amine are homologous.