In a reaction of $C_6H_5Y$,the major product obtained is the $60\%$ isomer. What is the group $Y$?

What is the product $X$ in the following Wurtz-Fittig reaction?

How will you convert $4-$nitrotoluene to $2-$bromobenzoic acid?

The product $(R)$ in the following synthetic scheme is

The compounds $P$,$Q$,and $S$ were separately subjected to nitration using $HNO_3 / H_2SO_4$ mixture. The major product formed in each case respectively,is

In the following reaction,the structure of the major product '$X$' is