c语言问题，我们老师要求改错，我实在不懂怎么改。。求大神

#include
void main()
{
 short x,y;
 float average;
 /**********found**********/
 scanf("%hd%hd",&x,&y)
  /**********found**********/
  average=(x+y)/2.0;  /*averaging the two numbers*/
/**********fpound**********/
 printf("average=%f\n",average);
}

#include 
#define PI (3.1415926)
int main()
{
    double r;
    scanf("%lf",&r);
    printf("%lf\n%lf\n",PI*2*r,PI*r*r);
    return 0;
}

#include 
#include 
int main()
{
    double deposit,capital,rate,n;
    rate=0.0295;
    capital=100000;
    n=2;
    deposit=capital*pow(1+rate,n);
    printf("%lf\n",deposit);
    return 0;
}

#include
void main()
{
short x,y;
float average;
/**********found**********/
scanf("%hd%hd",&x,&y)
/**********found**********/
average=(x+y)/2.0; /*averaging the two numbers*/
/**********fpound**********/
printf("average=%f\n",average);
}