The number of stereoisomers possible for a compound of the molecular formula $CH_3-CH=CH-CH(OH)-CH_3$ is:

At normal temperature,$X$ and $Y$ are:

The enol form in which ethyl $3$-oxobutanoate exists is

What is the relationship between the members of the following pairs of structures? Are they structural isomers,geometrical isomers,or resonance contributors?

In which of the following is the keto form more dominating than the enol form?

The correct statement$(s)$ concerning the structures $E, F$ and $G$ is (are):
$E$: $CH_3CH_2CH(CH_3)COCH_3$
$F$: $CH_3CH_2C(OH)=C(CH_3)_2$ (enol form)
$G$: $CH_3CH_2C(CH_3)=C(OH)CH_3$ (enol form)
$(A)$ $E, F$ and $G$ are resonance structures
$(B)$ $E, F$ and $E, G$ are tautomers
$(C)$ $F$ and $G$ are geometrical isomers
$(D)$ $F$ and $G$ are diastereomers