What is the total number of alkenes obtained in the following reaction?
$CH_3CH_2CH_2CH(OH)CH_3 \xrightarrow{H^+, \Delta} \text{Products}$

Decolourization of alkaline $KMnO_4$ is used as a test for

The major product $(P)$ formed in the below reaction is:
$CH_2$ attached to a cyclohexane ring $\xrightarrow[(ii) NaBH_4, OH^-]{(i) Hg(OAc)_2, H_2O-THF} P?$

Consider compounds $A$, $B$ and $C$ with following structural formulae: $A = CH_{3} - CH_{2} - CH_{2} - CH_{2} - CH_{2} - OH$, $B = CH_{2} = CH - CH_{2} - CH_{2} - CH_{3}$, $C = HO - CH_{2} - CH_{2} - CH(OH) - CH_{3}$. For the conversion of $B$ from $A$, reagent $(D)$ required is . . . . . . and structural formula of product $(E)$ obtained when $C$ undergoes same reaction using excess reagent $(D)$ is . . . . . . .

Assertion : $1$-Butene on reaction with $HBr$ in the presence of a peroxide produces $1$-bromobutane.
Reason : It involves the free radical mechanism.

Ozonolysis of which compound gives $OHC-CH_2-CH(CH_3)-CH_2-CHO$?