2.12. Prove Proposition 2.19. It simplifies matters to assume that the preferences involved are strictly monotone, as well as continuous, and you may make this assumption if you wish, although it isn't necessary to the proof. (Hint: Given this assumption, mimic the proof of Debreu's Theorem given in this chapter.)
2.13.Suppose к=2, and we have a consumer whose preferences are continuous and strictly monotone. If you are given a single indifference curve for this consumer, how much of her preferences can you construct if her preferences are also homothetic? What if, in addition to being strictly monotone and continuous, her preferences are quasi-linear in the second commodity?