What is the product of the following reaction?

Consider the following reaction sequence:
$2-\text{Methylpropane}$ $\xrightarrow{KMnO_4} X$ $\xrightarrow[358 \ K]{20 \% \ H_3PO_4} Y$ $\xrightarrow[\text{(ii) } Zn \mid H_2O]{\text{(i) } O_3} A + B$
What are $A$ and $B$?

Propene $CH_3CH=CH_2$ can be converted into propan$-1-$ol by oxidation. Indicate which set of reagents amongst the following is ideal to effect the above conversion?

$A$ compound '$X$' on ozonolysis forms two molecules of $HCHO$. Compound '$X$' is

In the following reaction,the major product is
$H_2C=C(CH_3)-CH=CH_2 \xrightarrow{1 \text{ equivalent } HBr}$

$CH_3-CH=CH_2$ $\xrightarrow{Br_2, hv (\text{low conc.})} \dots$ $\xrightarrow{Mg, \text{Dry ether}} \dots$ $\xrightarrow{CH_3-CO-CH_3, NH_4Cl} \dots$ $\xrightarrow{H^{+}, \Delta} (X)$. The end product $(X)$ of the above reaction is: