Which of the following units is used to form cross-linked silicone?

$SiF_4$ gets hydrolysed giving .......

Which of the following does $NOT$ give oxygen upon heating?

In the carbon family,elements other than carbon do not form $p\pi - p\pi$ bonds because their atomic radii are very ........

Match List-$I$ with List-$II$.

List-$I$	List-$II$
$A$. Coke	$I$. Carbon atoms are $sp^3$ hybridised
$B$. Diamond	$II$. Used as a dry lubricant
$C$. Fullerene	$III$. Used as a reducing agent
$D$. Graphite	$IV$. Cage like molecules

Choose the correct answer from the options given below:

In the following reaction,assign the product of complete hydrolysis at $R.T.$ for the underlined atom:
$\underline{Si}O_2 + H_2O \longrightarrow $ No reaction