How many transition states are formed during the following reaction?

p-Nitrotoluene on further nitration gives

Identify ‘Z’ in the following reaction series,CH3CH2CH2Br (X) (Y) (Z)

In which of the following reaction t–butylbenzene is formed

Which of the following structures correspond to the product expected, when excess of C6H6 reacts wit

CH≡C–COOH product (A), A is