1.
uses crt;
var a,b,h: integer;
begin
clrscr;
    writeln('===========Dien tich tam giac==========');
    write('Nhap chieu cao: '); readln(h);
    write('Nhap day: '); readln(a);
    writeln('Dien tich tam giac=',(a*h)/2:3:2);
    writeln('===========Dien tich hinh thang==========');
    write('Nhap chieu cao: '); readln(h);
    write('Nhap day lon: '); readln(a);
    write('Nhap day be: '); readln(b);
    writeln('Dien tich tam giac=',((a+b)*h)/2:3:2);
    readln
end.
2.
uses crt;
var d15,d45,dtx,dtx2,s: real;
begin
clrscr;
    write('Nhap diem 15 phut: '); readln(d15);
    write('Nhap diem 45 phut: '); readln(d45);
    write('Nhap 2 diem kiem tra thuong xuyen: '); readln(dtx,dtx2);
    s:=s+d15+d45+dtx+dtx2;
    writeln('Diem trung binh: ',(s/5):2:2);
    readln
end.