How many total isomers of aldehydes are possible for the molecular formula $C_5H_{10}O$?

Match List-$I$ with List-$II$.

List-$I$ Reaction	List-$II$ Reagents
$A$. Hoffmann Degradation	$I$. Conc. $KOH, \Delta$
$B$. Clemmensen reduction	$II$. $CHCl_3, NaOH / H_3O^{+}$
$C$. Cannizzaro reaction	$III$. $Br_2, NaOH$
$D$. Reimer-Tiemann reaction	$IV$. $Zn-Hg / HCl$

In the Claisen$-$Schmidt reaction to prepare dibenzalacetone from $5.3 \ g$ benzaldehyde,a total of $3.51 \ g$ of product was obtained. The percentage yield in this reaction was $......... \%.$

Reduction of ketones cannot be carried out with which of the following reagents?

Which of the following compounds does not give an Aldol condensation reaction?

Identify the reagents $(1-4)$ required for the transformations shown and arrange them in the correct order.
$(1)$ $LiAlH_4$
$(2)$ $OsO_4$
$(3)$ $NaIO_4$
$(4)$ $NaBH_4$