Ebonite is ........ .

Which of the following statements are correct?
$a$. Natural rubber becomes soft and sticky at high temperature.
$b$. Neoprene is a polymer of $2-$chloro$-1,3-$butadiene.
$c$. Nylon $6,6$ is a polyamide fibre.
$d$. Buna$-S$ is an example of a homopolymer.

Which of the following polymers is used in paints?

Which of the following statements is $NOT$ true about natural rubber?

Given below are two statements,one is Assertion $(A)$ and the other is Reason $(R).$
Assertion $(A):$ Natural rubber is a linear polymer of isoprene called cis-polyisoprene with elastic properties.
Reason $(R):$ The cis-polyisoprene molecules consist of various chains held together by strong polar interactions with a coiled structure.
In the light of the above statements,choose the correct one from the options given below:

Orlon has which monomeric unit?