Bài 3
Program CV_DT_HV;
Var a: integer;
     CV,DT: real;
Begin
  Writeln('canh cua hinh vuong la');
  Read(a);
  CV:=a*4;
  DT:=a*a;
  Writeln('chu vi hinh vuong la', CV:1:2);
  Writeln('dien tich hinh vuong la', DT:1:2);
Readln
End.

Bài 5
Program CV_D;
Var a,b: integer;
     CV,DT: real;
Begin
  Writeln('chieu dai cua hinh chu nhat la');
  Read(a);
  Writeln('chieu rong cua hinh chu nhat la');
  Read(b);
  CV:=(a+b)/2;
  DT:=a*b;
  Writeln('chu vi hinh chu nhat la', CV);
  Writeln('dien tich hinh chu nhat la', DT);
Readln
End.

Bài 6:
 program B_T;
var a:byte; 
begin 
writeln('nhap a'); 
readln(a); 
if ((a mod 2)=0) then writeln(a, 'la so chan'); 
if ((a mod 2)<>0) then writeln(a, 'la so le'); 
readln; 
end

Bài 7

Bài 9