Are based upon the following class declaration appearing in unknown.h All member function will be defined in the unknown.cpp class unknown {private: int a; public: unknown ();//Initializes a to 0 void seta (const int aa);//set a equal to aa void GetA(int & aa) const;//sends value of a to client through aa}; Which of the following is a valid implementation for setA? Void seta(int aa) const void unknown:: setA(aa) const void unknown::SetA() {aa=a;} {aa=a;} {a=aa;} void unknown::SetA(const int aa){a=aa;} none of the answer provided {a=aa;} Which of the following is a valid is a valid function heading for the function for the function unknown? Void unknown(); void unknown::unknown() unknown() int unknown::unknown() none of the answers provided Which of the following is a valid function heading for the function GetA? Int unknown::GetA(int& aa) void getA(int& aa) void unknown::GetA(int& aa)const None of the answers provided Suppose that a client program