Point out the error in the program

#include<stdio.h>
int f(in

Point out the error in the program

#include<stdio.h>
int f(int a)
 {
   a > 20? return(10): return(20);
 }
int main()
 {
     int f(int);
     int b;
     b = f(20);
     printf("%d\n", b);
     return 0;
 }

2) What will be the output of the program?

#include<stdio.h>
int func1(int);
int main()
 {
     int k=35;
     k = func1(k=func1(k=func1(k)));
     printf("k=%d\n", k);
     return 0;
 }
 int func1(int k)
 {
     k++;
     return k;
 }

3) What will be the output of the program?

#include<stdio.h>
int addmult(int ii, int jj)
 {
     int kk, ll;
     kk = ii + jj;
     ll = ii * jj;
     return (kk, ll);
 }
int main()
 {
     int i=3, j=4, k, l;
     k = addmult(i, j);
     l = addmult(i, j);
     printf("%d %d\n", k, l);
     return 0;
 }

4) Which of the following is not a library function:

5) What will be the output of the program?

#include<stdio.h>
#include<stdlib.h>
int main()
 {
     int i=0;
     i++;
     if(i<=5)
     {
         printf("Study2Online");
         exit(1);
         main();
     }
     return 0;
 }