The Bhopal gas tragedy of $1984$ was caused by

One among the following is the correct $IUPAC$ name of the compound $CH_3-CH_2-NH-CHO$.

What is the number of primary amine molecules among the following compounds?
$(CH_3)_3N, (CH_3)_2NH, CH_3-NH_2, CH_3-CH(NH_2)-CH_3, C_6H_5NH_2, C_6H_5NHCH_3, (CH_3)_3C-NH_2$

What is the main functional group in the compound shown in the image?

Match the following:

Column $I$	Column $II$
$(A)$ $CH_3CH_2CH_2CH_2NH_2$	$(i)$ Secondary amine
$(B)$ $(CH_3CH_2)_2NH$	$(ii)$ Tertiary amine
$(C)$ $(CH_3)_3N$	$(iii)$ Aromatic amine
$(D)$ $C_6H_5NH_2$	$(iv)$ Quaternary ammonium salt
	$(v)$ Primary amine

The correct match is:

The number of structural isomers possible from the molecular formula $C_3H_9N$ is