Which of the following compounds will not undergo tautomerism?

$A$ compound having molecular formula $C_3H_6O$,on reaction with $NH_2NHCONH_2$ produces mainly $P$ (which shows stereoisomerism). $P$ on reaction with $KOH$ / ethylene glycol,$\Delta$ produces propane. Identify $(P)$.

An organic compound $(X)$ has an empirical formula $C_4H_8O$. This gives a pale yellow precipitate with iodine in $NaOH$ solution. What is $X$?

Arrange the following in increasing order of their reactivity for nucleophilic addition reaction:

In the given reaction sequence, the percentage of oxygen in compound $(Q)$ is . . . . . . $\%$. (Nearest integer)

Given below are two statements,one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$: $3$-chloro-$2$-methylpentan-$3$-one can be subjected to Wolff-Kishner reduction to give $3$-chloro-$2$-methylpentane.
Reason $R$: Wolff-Kishner reduction is used to convert $C=O$ into $CH_2$.