A polymer sample contains 3 molecules of molar mass $10^3, 3$ molecules of molar mass 500 and 4 molecules of molar mass 200 . What is it's weight average molecular mass?

$$ \text { Match the following } $$

List-I (Polymer)		List-II (Monomers)
(A)	Bakelite	(I)	$$ \text { 2-methvl-1, 3-butadiene } $$
(B)	Natural rubber	(II)	$$ \text { Glvcine + aminocaproic acid } $$
(C)	Glyptal	(III)	$$ \text { Phenol + formaldehyde } $$
(D)	Nylon 2-nylon 6	(IV)	$$ \text { Phthalic acid + ethylene glycol } $$

Amongst the following, how many of them come under the category of elastomers? Natural rubber, polyethene, vulcanized rubber, bakelite, polyvinylchloride, buna-N, nylon-6, neoprene

$$ \text { The structure given below is an example of } $$

I. A condensation and biodegradable polymer.

II. A biodegradable and thermoplastic polymer.

III. A biodegradable and thermosetting polymer.

IV. A polyester and thermoplastic polymer.