var Imagen = new Array();
var Imageb = new Array();

for (var i = 0; i < 7; i++){
  Imagen[i] = new Image();
  Imagen[i].src = "pics/bn" + i + ".jpg";
}
for (var i = 0; i < 7; i++){
  Imageb[i] = new Image();
  Imageb[i].src = "pics/bb" + i + ".jpg";
}

function pic(IN) {
  var s = 'b' + IN;
  var t = 'pics/bb' + IN + '.jpg';
  document.getElementById(s).src = t;
  document.getElementById(s).style.cursor='hand'
}  

function pic2(IN) {
  var s = 'b' + IN;
  var t = 'pics/bn' + IN + '.jpg';
  document.getElementById(s).src = t;
}