Which bitwise operator is suitable for turning off a particular bit in a number?

Which bitwise operator is suitable for turning off a particular bit in a number?

2) What is the value of x in this C code?

#include <stdio.h>
     void main()
     {
         int x = 5 * 9 / 3 + 9;
     }

3) What is the output of this C code?

#include <stdio.h>
     int main()
     {
         int i = -3;
         int k = i % 2;
         printf("%d\n", k);
     }

4) Consider the following program segment:

 main()
 {
   int a,b,c;
   b=3;
   a=2;
   a=2*(b++);
   c=2*(++b);
 }

5) What is the output of this C code?

#include <stdio.h>
     int main()
     {
         int x = 2, y = 2;
         x /= x / y;
         printf("%d\n", x);
         return 0;
     }