$C_8H_{16}$ that can form cis-trans geometrical isomers and also has a chiral centre,is

$17 \, mg$ of a hydrocarbon ($M$.$F$. $C_{10}H_{16}$) takes up $8.40 \, mL$ of $H_2$ gas measured at $0^{\circ}C$ and $760 \, mm$ of $Hg$. Ozonolysis of the same hydrocarbon yields acetone,formaldehyde,and a compound with the structure $CH_3-CO-CH_2-CH_2-CHO$. The number of double bonds present in the hydrocarbon is $...........$.

For the given reaction:
(Cyclohexyl)-$CH$=$CH$-(Cyclohexyl) $\xrightarrow{KMnO_4/H^+}$ '$P$' (major product)
'$P$' is:

Acetone is formed by the ozonolysis of which of the following?

Find the stability order of the following compounds:

Alkene $(x)$ $\xrightarrow[\Delta ]{KMnO_4/H^+}$ gives the following products:
$x$ is