Which of the following is not a semi-synthetic polymer?

$Buna-S$ is an example of:

Differentiate between rubbers and plastics on the basis of intermolecular forces.

Define thermoplastics and thermosetting polymers with two examples of each.

Write the names of monomers of the following polymers:
$(i)$ $-(NH-(CH_2)_6-NH-CO-(CH_2)_4-CO)_n-$
$(ii)$ $-(CO-(CH_2)_5-NH)_n-$
$(iii)$ $-(CF_2-CF_2)_n-$

Nylon is an example of