The “N” which does not contribute to the basicity for the compound is :

Which of the following is a bactericidal antibiotic ?

Observation of “Rhumann’s purple” is a confirmatory test for the presence of :

Let P = {$$\theta $$ : sin$$\theta $$ $$-$$ cos$$\theta $$ = $$\sqrt 2 \,\cos \theta $$}

and Q = {$$\theta $$ : sin$$\theta $$ + cos$$\theta $$ = $$\sqrt 2 \,\sin \theta $$} be two sets. Then