Product $(A)$ is

The cycloalkane $(X)$ on bromination consumes one mole of bromine per mole of $(X)$ and gives product $(Y)$ in which $C:Br$ ratio is $3:1$. The percentage of bromine in the product $(Y)$ is $ . . . . . . \%$ (Nearest integer).
(Given: Molar mass in $g \ mol^{-1}$,$H:1, C:12, O:16, Br:80$)

Identify the product $B$ in the following reaction sequence:
$1,4-\text{cyclohexadiene-1,4-dicarboxylic acid}$ $\xrightarrow{NaOH} A$ $\xrightarrow{\text{Kolbe electrolysis}} B$

Compound $A$ $(C_{11}H_{14}O_4)$ is a degradation product of the antibiotic vermiculine. It undergoes the following reactions as shown in the image. Identify the unknown compound $C$ $(C_{11}H_{18}O_2)$.

Natural petroleum contains

Which of the following is not a mixture of hydrocarbons?