Paste code

#include <stdio.h>
#include <conio.h>
#define PI 3.14
int main()
{
	
	//nhap ban kinh cua duong tron. tinh chu vi va dien tich cua hinh tron do 
	float bankinh;
	float chuvi , dientich;
	printf("\nnhap vao ban kinh : ");
	scanf("%f", &bankinh);

        chuvi = bankinh * 2 * PI;
	dientich =bankinh * bankinh * PI;

	printf("\nchu vi = %f",chuvi);
	printf("\ndien tich = %f",dientich);


   getch();
   return 0;


}