Which aromatic compound possesses a seven-membered ring?

$Ethyl$ benzene cannot be prepared by:

If $p$-methoxytoluene is nitrated,the major product is:

Using anhydrous $AlCl_3$ as a catalyst,which one of the following reactions produces ethylbenzene $(PhEt)$?

The total number of structural isomers possible for the substituted benzene derivatives with the molecular formula $C_9H_{12}$ is $.........$

The major product obtained in the reaction of toluene with $1-$bromo$-2-$methylpropane in the presence of anhydrous $AlCl_3$ is