21.2FE (Give you reasoning behind your choice) A completely amorphous and nonporous\ polymer will be:\ (A) transparent (C) opaque\ (B) translucent (D) ferromagnetic\ How about a semi-crystalline polymer with no porosity? Please consider two cases: 1)\ strain-free; 2) 30% strained without post annealing. Indicate other appropriate answers if\ the above choices are all unreasonable. Use sketches or equations if necessary (Provided\ by Prof. Gao)