Dry heating of calcium acetate gives

In the reaction $RMgBr + HC(OEt)_3 \xrightarrow{Ether, H_3O^{+}} P$, the product $P$ is

What is $A$ in the following reaction?
$CH_3-CH=CH-CH_2-CH_2-CN \xrightarrow[\text{2) } H_2O]{\text{1) } AlH(i-Bu)_2} (A)$

In the Rosenmund's reduction,$BaSO_4$ taken with catalyst $Pd$ acts as

Give the conversion of the following:
$(i)$ Lactic acid from ethanal
$(ii)$ $p-$fluorobenzaldehyde from $p-$fluorotoluene

In the following sequence of reactions:
$C_6H_5CH_3$ $\xrightarrow{KMnO_4} A$ $\xrightarrow{SOCl_2} B$ $\xrightarrow{H_2/Pd, BaSO_4} C$
the product $C$ is: