[10 points] If a polymer has a density of 1.8g/cm3 for a material that has 50% (weight % ) crystalline material, and an all amorphous material has a density of 1.68g/cm3, what would be an all-crystalline polymer density be? Explain why scientists and engineers haven't been able to achieve a 100% crystalline material. Name two things that could help increase crystallinity in a material