What are the advantages of using JavaScript libraries (like jQuery) to implement Ajax?

The primary benefit of using AJAX techniques in a web application is:

Which method on the XMLHttpRequest object is used to send custom HTTP headers with a request?

What is the value of the "status" attribute of the completed XMLHttpRequest object if the Ajax request has pulled the response data from the browser cache? Consider only non-IE browsers.

The onreadystatechange change event is used to invoke behavior when

If an Ajax request loads JSON-formatted responseText into the variable returnedData, what code will turn the data into a readable JSON object in modern browsers, including IE8 and above?

To check if DOM element 'currentDiv' don't have any child nodes, we can use which one of the following conditions?

Which method is NOT supported by the XMLHttpRequest object?

By default, browsers do not support cross domain AJAX requests.

(function worker() { $.ajax({ url: 'ajax/test.html', success: function(data) { $('.result').html(data); }, complete: function() { setTimeout(worker, 5000); } }); })();

choose the option that shows the output to the console log