B1:

program Hinh_vuong;

uses crt;

var a,C,S:integer;

begin

write('nhap a:');readln(a);

C:=a*4;

S:=a*a;

writeln('chu vi hinh vuong la:',C);

writeln('dien tich hinh vuong la:',S);

readln;

end.

B2:

program trung_binh_cong;

uses crt;

var a,b,c,d,e,S:integer;

begin

write('nhap a:');readln(a);

write('nhap b:');readln(b);

write('nhap c:');readln(c);

write('nhap d:');readln(d);

write('nhap e:');readln(e);

S:=(a+b+c+d+e)/5;

writeln('trung binh cong la:',S);

readln;

end.

1.

program ct;
uses crt;
var a,cv,dt: Qword;
begin
    clrscr;
    writeln('Nhap do dai canh'); readln(a);
    cv:=a*4; dt:=a*a;
    writeln('Chu vi hinh vuong la: ',cv);
    writeln('Dien tich hinh vuong la: ',dt);

end.

2.

program ct2;
uses crt;
var a,b,c,d,e: real;
begin
    clrscr;
    writeln('Nhap a,b,c,d,e: '); readln(a,b,c,d,e);
    writeln; writeln('Trung binh cong cua 5 so tren la: ',(a+b+c+d+e)/5:5:2);
    readln;
end.

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