Which of the following can work as a dehydrating agent for alcohols?

Identify the major product $P_3$ in the following reaction sequence:

Which sequence of steps describes the best synthesis of $2-$phenylpropene?

The compound $A$ on treatment with $Na$ gives $B$,and with $PCl_{5}$ gives $C$. $B$ and $C$ react together to give diethyl ether. $A, B$ and $C$ are in the order

Predict the major product of the following reaction:

$CH_3MgBr + \text{Cyclopentanone}$ $\xrightarrow{H_3O^{+}} A$ $\xrightarrow{HBr} B$ $\xrightarrow{Mg/\text{ether}} C$ $\xrightarrow{HCHO}_{H_3O^{+}} D$ $\xrightarrow{HI} E$
$E$ is