A low molecular weight plasticizer with Tg = -49C is added to a virgin polystyrene (PS) resin to improve its flexibility. Assume that a single phase is maintained upon plasticization. Q12A) What weight percent of the plasticizer must be added in order for the Tg of the PS to be reduced from 100C to 88C? Q12B) If the Mn of the virgin PS is 66,500 g/mol, and that of the plasticizer is 3,500 g/mol, what would be the resultant Mn of the plasticized PS from part Q12A? Q12C) If the same virgin PS (Mn = 66,500 g/mol) has an ultimate tensile strength of 45 MPa, and another lower molecular weight PS (Mn = 20,000 g/mol) has an ultimate tensile strength of 30 MPa, calculate the ultimate tensile strength of the plasticized PS from part Q12B in units of [MPa]