For the question below, use these symbols correspondingly:

Preference relation: ?

Strictly preferred to: ?

Indifference: ~

Is a subset of: ? i.e. A ? B means A is a subset of B

Please bold things like R (real numbers), R+means positive real numbers, vice versa.

4. The notion of convex preferences is very important in economics, capturing the idea that a consumer likes "balanced" bundles of goods. This question gives you some practice reasoning about convex preferences. For each of the preferences relations YES, 21, 12, _L defined in the previous question, is the relation convex? Justify your answer. (a) YES? (b) z1? (c) -2? (d) zz