function showimage(path, width, height) {
  if (width == 0 || height == 0) {
    alert("Картинка не назначена");
    return false;
  }
  sb = "auto";
  width += 20;
  if (width < 350) {
    width = 350;
    sb = "no";
  }
  if (width > 1000) {
    width = 1000;
    sb = "yes";
  }
  height += 100;
  if (height < 320) {
    height = 320;
    sb = "no";
  }
  if (height > 650) {
    height = 650;
    sb = "yes";
  }
  window.open(path, 'imagewindow', 'left=20,top=20,height=' + height + ',width=' + width + ',menubar=no,resizable=yes,status=no,scrollbars=' + sb);
}

function show_answer(id, arr_id) {
  if (document.getElementById(id).style.display == "") {
    document.getElementById(id).style.display = "block";
  } else if (document.getElementById(id).style.display == "none") {
    document.getElementById(id).style.display = "block";
  } else if (document.getElementById(id).style.display == "block") {
    document.getElementById(id).style.display = "none";
  }
}