function highdld(i) {
  butDld0 = new Image(); butDld0.src = 'images/dld_0.gif';
  butDld1 = new Image(); butDld1.src = 'images/dld_1.gif';
  butBuy0 = new Image(); butBuy0.src = 'images/buy_big0.gif';
  butBuy1 = new Image(); butBuy1.src = 'images/buy_big1.gif';
}