program spanningsversterking; uses wincrt;
var
   Uin, Uuit, AdB: real;
function log(x: real): real;
   begin
      log:=ln(x)/ln(10)
   end;
begin
   write('Geef waarde Uin in volt: ');
   read(Uin);
   write('Geef waarde Uuit in volt: ');
   read(Uuit);
   AdB:=20*log(Uuit/Uin);
   write('Spanningsversterking is: ', AdB:8:2, ' dB')
end.