Which is a biodegradable polymer?

Which polymer is obtained from monomers $3-$Hydroxybutanoic acid and $3-$Hydroxypentanoic acid?

$A$ polymer sample contains $10$ molecules each with molecular mass $5,000$ and $5$ molecules each with molecular mass $50,000$. The number average molecular mass of the polymer sample is

Bulletproof helmets are made from -

Which of the following polymers possesses strong intermolecular forces like hydrogen bonding?

Which among the following statements about $HDP$ is $NOT$ true?