Explain the following code assuming using declarations for all the members of namespace Ex...

Explain the following code assuming using declarations for all the members of namespace Exercise are located at the location labeled position 1. What if they appear at position 2 instead? Now answer the same question but replace the using declarations with a using directive for namespace Exercise.

namespace Exercise {    int ivar = 0;    double dvar = 0;    const int limit = 1000;}int ivar = 0;// position 1void manip() {    // position 2    double dvar = 3.1416;    int iobj = limit + 1;    ++ivar;    ++::ivar;}