1.55(a)
What is the best way to find the restriction on alpha and f(y) such that v(p,y) is quasiconvex in (p,y)?
Should I use the boarder Hessian?

1.57
Given the expenditure function, I solve for the indirect utility function. Then by Roy's identity, I can solve for the Marshallian demand and hence income elasticity. But I still couldn't answer the question. My income elasticity is a bit messy. Am I on the right track? Moreover, I haven't used the fact that a(p) and b(p) are concave.

1.58
What is the best way to find the restriction on the given expenditure function (e(p,u)) such that it is concave in p?

Please guide me. Thank you.