Accessing variables with the same name at different scopes [duplicate]

Answer 1

No you can't, a (2) is hidden.

Ref: 3.3.7/1

A name can be hidden by an explicit declaration of that same name in a nested declarative region or derived class (10.2).

Ref: 3.4.3/1

The name of a class or namespace member can be referred to after the :: scope resolution operator (5.1) applied to a nested-name-specifier that nominates its class or namespace. During the lookup for a name preceding the :: scope resolution operator, object, function, and enumerator names are ignored. If the name found is not a class-name (clause 9) or namespace-name (7.3.1), the program is ill-formed.

Answer 2

Short answer: no. You are basically overriding the inherited scope of a locally, and it will use that local copy over any inherited ones.

Basically like a child object overriding a function or variable of the parent object, it will use it's copy of it regardless of what the parent had.