1.cin is a function2. 3. You can tell the compiler to use the global identifier rather than the local identifier by prefixing the identifier with :: the scope resolution operator#include using namespace std;int amount 123; // A global variableint main() { int amount 456; // A local variable cout << ::amount << endl // Print the global variable << amount << endl; // Print the local variable}4.In some cases inline functions make a compute-bound application run faster.5.When an object is passed by value returned by value or explicitly copied. Copy Constructor is invoked. Basically It is invoked implicitly by the compiler.6.