Consider the following properties of a Banach space: 

the intersection of any support hyperplane with the unit sphere is 

(S) a singleton (this is the strict convexity);

(SF) finite-dimensional set;

(SC) compact in the norm topology.

It is easy to see that these properties are equivalent to the fact that any closed convex subset of a unit sphere is singleton/finite-dimensional/ compact.

   Q1: Are (SF) and (SC) different?

   Q2: Were these conditions considered in the literature? Do they have names?

   Q3: Are there any necessary or sufficient conditions for them? In particular, are there any dual/predual conditions?