Begin Clrscr; Write ('Nhap ban kinh R: '); readln(r); dt:=pi*r*r; cv:=2*pi*r; Writeln('Dien tich hinh tron la:',dt:1:2); Writeln('Chu vi hinh tron la:',cv:1:2); Readln;
program BTH; uses crt; var a:real; BEGIN clrscr; Write('Nhap ban kinh: ');readln(a); Writeln('Chu vi hinh tron la: ',(a+a)*pi:4:2); writeln('Dien tich hinh tron la: ',a*a*pi:4:2); readln; END.
