Which of the following substances resists the nucleophilic attack of $OH^{-}$ ions?

Identify the products $(X, Y)$ and reaction mechanism $(Z)$ of the following reaction:
$CH_3CH_2-O-C(CH_3)_2CH_2CH_3 \xrightarrow{HI, \Delta} X + Y$

Diethyl ether absorbs oxygen to form

Methyl vinyl ether,$H_2C=CH-OCH_3$,reacts with $Br_2/CH_3OH$. If methanol is reacting as water would,and if this reaction follows a typical mechanism of electrophilic addition,what would be the expected product?

Isopropyl methyl ether when treated with cold hydrogen iodide $(HI)$ gives -

Identify the product$(s)$ formed in the following reaction.