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 fun(int);
int main()
 {
     float k=3;
     fun(k=fun(fun(k)));
     printf("%f\n", k);
     return 0;
 }
int fun(int i)
 {
     i++;
     return i;
 }

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) 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;
 }

5) Point out the error in the program

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