4. Kristin's has $20 to spend on two soft-drinks, Poke (P) and Cepsi (C), that she enjoys. The two drinks are very similar, so Kristin's preferences for them can be represented by the following utility function: U (P, C) =4P+3C. a) If the price of Poke and Cepsi is $1 and $2 per can, respectively, how much of each will Kristin choose to buy? b) Suppose the price of Cepsi falls from $2 to $1.50. What will happen to Kristin's optimal consumption of Poke and Cepsi? Explain your answer carefully. c) Describe what will happen to Kristin's optimal consumption if the price of Cepsi continues to fall