Which HTML5 doctype declarations are correct?

Consider the following JavaScript code: var c=document.getElementById('myCanvas'); var ctx=c.getContext('2d'); var img=document.getElementById('img'); Which method will correctly draw an image in the x=10, y=10 position?

How can an HTML5 canvas size be changed so that it fits the entire window?

Which is an invalid value for the type attribute of a command tag?

Difference between Server-Sent Events (SSEs) and WebSockets in HTML5?

What is the proper syntax for a line break tag as W3C specs define?

What is the proper syntax for specifying a cache manifest?

Which of the next video formats is not entirely available for Firefox Browsers?

Which attribute should be used to indicate that a <time> element represents the date of a blog post?

Which of the following is NOT a valid value for the <iframe> sandbox attribute in HTML 5.0?

Which of these is NOT one of the five different element types?