Isomeric amines with molecular formula C $_8$ H $_{11}$ N give the following tests Isomer (P) $\Rightarrow$ Can be prepared by Gabriel phthalimide synthesis Isomer (Q) $\Rightarrow$ Reacts with Hinsberg's reagent to give solid insoluble in NaOH Isomer (R) $\Rightarrow$ Reacts with HONO followed by $\beta$-naphthol in NaOH to give red dye. Isomers (P), (Q) and (R) respectively are