1. Write a program which input three numbers (int a.b.c ; cin>a>b>c; ) and calculate the average of three numbers (int averag =(a+b+c)/3; ). Output your result. 3.(Optional) Write a program which accepts a character (char ch: cin ch;) and display its next character(char next =++ ch; cout ? a) directive b) pre-processor directive c) file 2. If we were to not declare using namespace std, could we still somehow use cout and cin? a) Yes b) No 3. What would be required to use cout withouth declaring namespace a) Nothing b) std::cout