$A \xleftarrow[\Delta]{Cu} CH_3CH_2OH \xrightarrow[\Delta]{Al_2O_3} B$. $A$ and $B$ respectively are

What is the major product of the following reaction?

The disappearance of the characteristic purple colour of $KMnO_4$ in its reaction with an alkene is the test for unsaturation. It is known as

Write the main product of the given reactions:
$(1)$ $CH_3-CH=C(CH_3)_2 + HCl \to$
$(2)$ $3-\text{Methylbut-}1-\text{ene} + HBr \to$

Select the incorrect option based on the given reactions:
Reaction $1$: Methylenecyclohexane + $dil. H_2SO_4 \rightarrow (P)$ (major product)
Reaction $2$: $1-$Methylcyclohexanol + $dil. H_2SO_4 \rightarrow (Q)$ (major product)

$A$ hydrocarbon with molecular formula $C_6H_{10}$ absorbs only one molecule of $H_2$ upon hydrogenation. Ozonolysis of the hydrocarbon yields $OHC-CH_2-CH_2-CH_2-CH_2-CHO$. The hydrocarbon is: