Which among the following is correct structure of the semicarbazone formed when ethanal reacts with semicarbazide?

The $\mathrm{IUPAC}$ name for the following compound is

What are the products formed in the reaction given below:

$\mathrm{Ph}-{\mathrm{CH}}_2-\mathrm{CH}=\mathrm{CH}-{\mathrm{CH}}_3\underset{{}^{\mathrm{Zn} \mathrm{dust}+{\mathrm{H}}_2\mathrm{O}}}{\overset{1){\mathrm{O}}_3}{\to }}$?

The major product of the following reaction sequence is

The major products $\mathrm{P}$ and $\mathrm{Q}$ in the following reaction sequence are