5. For the next few questions, here is the basic environment. Xavier's inverse demand for science fiction books is given by: P = " - 4, where mis Xavier's income. Vivian's inverse demand for science fiction books is given by: P= " - 4. Xavier and Vivian are the only buyers of this product in their town. You also know that Xavier's income is higher than Vivian's: m* = 4mV. Which of the following is the aggregate demand function, DA(P, m ), where A stands for aggregate? (a) DA(P, mv) = AmV - AP if P> mv /2 5mV -6P if0 m /2 12mV - AP ifOSP m /2 2my - AP ifOSP mv /2 2my - AP if0