2 câu trả lời
uses crt;
var r:real;
begin
clrscr;
readln(r);
writeln(r * r * pi:0:2);
writeln(r * 2 * pi:0:2);
readln;
end.
Program BAI_TINH_HINH_TRON;
Uses Crt;
Var r,S,C:real;
Begin
Clrscr;
Writeln('TINH DIEN TICH VA CHU VI HINH TRON:');
Write ('Moi ban nhap ban kinh R=');
readln(r);
S:=pi*r*r;
C:=2*pi*r;
Writeln('Dien tich hinh tron la:',S:4:2);
Writeln('Chu vi hinh tron la:',C:4:2);
Readln;
End.