A gene delivery startup company has asked you to help design some polymers to deliver a proprietary gene they recently developed. After some literature search you found two classes of polymers: poly (beta amino alcohols) (PBAAs) as described in "Ma et al. Advanced Materials 2011, 23, H189." and poly (beta amino esters) (PBAEs) as described in "Anderson et al. Molecular Therapy 2005, 11, 426." a) Go through these two papers and briefly describe (1) how the PBAAS and PBAEs are made; (2) which class of polymers are you going to choose for gene delivery and why. [5 pt] b) As you may note in both cases, each of the monomers has 2 reactive, functional groups, which is typically required for step-growth polymerization. Suppose the numbers of monomers you initially have at t=0 are Ao for monomer a-a and Bo for monomer b-b. Now you let the monomers polymerize for a period of time t and the numbers of monomers left are A, for monomer a-a and B, for monomer b-b. (1) What are the conversions for monomer a-a and monomer b-b? (2) Now assuming Ao-Bo, how is molecular weight of the polymer related to the conversion? (Try to be quantitative and clearly state any assumptions you make.) (3) In real world applications, Ao and Bo may be different. Define their ratio (i.e. Stoichiometric ratio) r=A/Bo