In the Liebermann nitroso reaction,what is the sequence of color changes in phenol?

Aspirin is the acetylation product of .......

Which among the following is a dihydric phenol?

What is the correct order of acidity for the following compounds?

$A$ trisubstituted compound '$A$',$C_{10}H_{12}O_2$ gives a neutral $FeCl_3$ test positive. Treatment of compound '$A$' with $NaOH$ and $CH_3Br$ gives $C_{11}H_{14}O_2$,with hydroiodic acid $(HI)$ gives methyl iodide,and with hot conc. $NaOH$ gives a compound $B$,$C_{10}H_{12}O_2$. Compound '$A$' also decolorises alkaline $KMnO_4$. The number of $\pi$ bonds present in the compound '$A$' is $...........$

Among the following,the compound that undergoes nitration readily is