Комбинированный тип данных, надо подправить пару строк

unit Unit1;
 
interface
 
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;
 
type
  TForm1 = class(TForm)
    Edit1: TEdit;
    Edit2: TEdit;
    Edit3: TEdit;
    Memo1: TMemo;
    Button1: TButton;
    Button2: TButton;
    ComboBox1: TComboBox;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
 
var
  Form1: TForm1;
 
implementation
const n=3;
type
student=record
fam: string  ;
Mark: record
algebra, history, prog: 1..5;
end;
end;
 
var group: array[1..5] of student;
s1: student;
i1,b,c,a:integer;
sum:real;
algebra,history,prog: real;
 
{$R *.dfm}
 
procedure TForm1.Button1Click(Sender: TObject);
begin
algebra:=a;
history:=b;
prog:=c;
with s1 do
begin
fam:=combobox1.Items[combobox1.ItemIndex];
with mark do begin
a:=strtoint (edit1.text);
b:=strtoint (edit2.Text);
c:=strtoint (edit3.Text);
end;
group[i1]:=s1;
end;
i1:=i1+1;
end;
 
procedure TForm1.Button2Click(Sender: TObject);
var i:integer;
begin
              memo1.Clear;
              for i:=0 to 4 do
              begin
              with group[i] do
              begin
              memo1.LineS.Add (fam);
              memo1.Lines.add('');
              sum:=floattostr(a+b+c/n);
 
end ;  end;
 
end;
 
end.

Program Forum_Example;
 type
  Student=record
   Name,SurName,Pacronomic:String[20];
   Fizika,Algebra,English:integer;
   Sr:real;
  end;
 var
  M:array[1..5] of Student;
  i:integer;
begin
 For i:=1 to 5 do
  begin
    Read(M[i].Name);
    Read(M[i].Surname);
    Read(M[i].Pacronomic);
     Read(M[i].Fizika);
     Read(M[i].Algebra);
     Read(M[i].English);
      M[i].Sr:=(M[i].English+M[i].Algebra+M[i].Fizika)/3;
  end;
 
 For i:=1 to 5 do
   if M[i].Sr>4.5 then
    Writeln(M[i].Name,'   ',M[i].Sr);
Readln;
end.