The total number of isomeric trimethylbenzene is

Among the following,the total number of meta-directing functional groups is $ . . . . . . $ (Integer based).
$-OCH_3, -NO_2, -CN, -CH_3, -NHCOCH_3, -COR, -OH, -COOH, -Cl$

Which of the following is not an aromatic compound?

$x =$ Number of aromatic compounds obtained when the above compound undergoes complete acidic hydrolysis.

Given below are two statements,one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$ : Benzene is more stable than hypothetical cyclohexatriene.
Reason $R$ : The delocalized $\pi$ electron cloud is attracted more strongly by nuclei of carbon atoms.
In the light of the above statements,choose the correct answer from the options given below:

$n$-heptane $\xrightarrow[600\ {}^oC]{Cr_2O_3/V_2O_5}$ ?