Which of the following shows only one monobrominated compound upon reaction with $Br_2$ in the presence of light?

The major product formed in the following reaction is:
$CH_3-CH(CH_3)-CH_3 \xrightarrow[CH_3OH]{CH_3OBr}$

What does petroleum mainly consist of?

Which isomer of $C_6H_{14}$ has the highest boiling point?

In the bromination of isobutane,the relative reactivity rates of $1^oH, 2^oH,$ and $3^oH$ are $1 : 82 : 1600$ respectively. Calculate the percentage yield of products $(a)$ and $(b)$ in the following reaction:
$CH_3-CH(CH_3)-CH_3 (excess) + Br_2 \xrightarrow{hv} (a) CH_3-C(Br)(CH_3)-CH_3 + (b) CH_3-CH(CH_3)-CH_2Br$

The best method for the preparation of $2, 2-$dimethylbutane is via the reaction of