The catalyst used for olefin polymerization is

Which one of the following polymers is prepared by addition polymerisation?

Identify the condensation homopolymer from the following:

The expected reactivity of the monomers shown below towards cationic polymerization follows the order:
$I: CH_2=CH-CO_2CH_3$
$II: CH_2=CH-Cl$
$III: CH_2=CH-CH_3$
$IV: CH_2=CH-Ph$

Polymer formation from monomers starts by

Which of the following polymerisation reactions leads to the formation of neoprene?