3-Methylhex-2-ene on reaction with $$\mathrm{HBr}$$ in presence of peroxide forms an addition product (A). The number of possible stereoisomers for '$$\mathrm{A}$$' is ________.

Among the given organic compounds, the total number of aromatic compounds is

Among the following, total number of meta directing functional groups is (Integer based)

$$-\mathrm{OCH}_3,-\mathrm{NO}_2,-\mathrm{CN},-\mathrm{CH}_3-\mathrm{NHCOCH}_3, -\mathrm{COR},-\mathrm{OH},-\mathrm{COOH},-\mathrm{Cl}$$

The number of electrons present in all the completely filled subshells having $$\mathrm{n}=4$$ and $$\mathrm{s}=+\frac{1}{2}$$ is _______.

(Where $$\mathrm{n}=$$ principal quantum number and $$\mathrm{s}=$$ spin quantum number)