Bài 7: 
Program NN;
Uses crt;
Var n: longint;
Begin
        Clrscr;
        Write('Nhap n: '); Readln(n);
        If n mod 2 = 0 then Write('Chan')
        Else Write('Le');
        Readln
End.
Bài 8: Program NN;
Uses crt;
Var n: longint;
Begin
        Clrscr;
        Write('Nhap n: '); Readln(n);
        If n > 0 then Write('Duong')
        Else If n < 0 then Write('Am')
        Else Write('Khong am khong duong');
        Readln
End.
Bài 5:
Program NN;
Uses crt;
Var a,b,c: real;
Begin
        Clrscr;
        Write('Nhap do dai 3 canh: '); Readln(a,b,c);
        If (a+b>c) and (b+c>a) and (a+c>b) then Write('YES')
        Else Write('NO');
        Readln
End.
Bài 6:
Program NN;
Uses crt;
Var a,b,c: real;
Begin
        Clrscr;
        Write('Nhap do dai 3 canh: '); Readln(a,b,c);
        If (a+b>c) and (b+c>a) and (a+c>b) then
        Begin
                If (sqr(a)+sqr(b)=sqr(c)) or (sqr(b)+sqr(c)=sqr(a)) or (sqr(a)+sqr(c)=sqr(b)) then
                Write('YES')
                Else Write('NO');
        End
        Else Write('Khong phai tam giac');
        Readln
End.
Bài 3: Không thấy rõ đề
Bài 4: 
Program NN;
Uses crt;
Const pi=3.14;
Var a,b,r,s: real;
Begin
        Clrscr;
        Write('Nhap a,b: '); Readln(a,b);
        r:=sqrt(sqr(a)+sqr(b));
        s:=sqr(r)*pi;
        Write('S = ',s:0:2);
        Readln
End.

Bài 7:

uses crt;
var n:longint;
begin
clrscr;
   write('n=');readln(n);
   if n mod 2=0 then writeln(n,' la so chan') else writeln(n,' la so le');
readln
end.

Bài 8:

uses crt;
var n:longint;
begin
clrscr;
   write('n=');readln(n);
   if n>0 then writeln(n,' la so duong') else
   if n<0 then writeln(n,' la so am') else
   writeln(n,' la so nguyen 0');
readln
end.

Bài 5:

uses crt;
var a,b,c:longint;
begin
clrscr;
   write('a,b,c=');readln(a,b,c);
   if(a+b>c)and(a+c>b)and(b+c>a) then writeln('Yes') else writeln('No');
readln
end.