What is the major product obtained when calcium acetate and calcium formate are heated together?

What are $X$ and $Y$ in the following reaction sequence ?
$C_6H_5N_2^+Cl^{-}$ $\xrightarrow{X} C_6H_5CN$ $\xrightarrow[\text{(ii) } H_2O]{\text{(i) } CH_3MgBr} Y$

The chemicals used for preparing acetophenone are:
$(A)$ $C_6H_6$
$(B)$ $CH_3COCH_3$
$(C)$ $CH_3COCl$
$(D)$ Anhydrous $AlCl_3$

An organic compound $X$ gives a red precipitate on heating with Fehling's solution. Which one of the following reactions yields $X$ as a major product?

$Benzaldehyde$ can be obtained from $benzal$ chloride. Write reactions for obtaining $benzal$ chloride and then $benzaldehyde$ from it.

$X$ & $Y$ respectively are $-$