<!DOCTYPE html>
<html>
<head>
<style>
table {
width: 100%;
}
table, th, td {
border: 1px solid black;
}
</style>
</head>
<body>
<p>Click the button to change the value of the headers attribute of td with id "myTd".</p>
<table>
<tr>
<th id="name">Name</th>
<th id="email">Email</th>
<th id="phone">Phone</th>
<th id="addr">Address</th>
</tr>
<tr>
<td id="myTd" headers="name">John Doe</td>
<td headers="email">someone@example.com</td>
<td headers="phone">+45342323</td>
<td headers="addr">Rosevn 56,4300 Sandnes,Norway</td>
</tr>
</table>
<br>
<button onclick="myFunction()">Try it</button>
<p id="demo"></p>
<script>
function myFunction() {
document.getElementById("myTd").headers = "newValue";
document.getElementById("demo").innerHTML = "The value of the headers attribute was changed from 'name' to 'newValue'.";
}
</script>
</body>
</html>