Is the width=100, then it should be width=100% ? Yes Or No

Answer 1

In html attributes ( because of the 'html' tag and the equal sign ), no specifying units means implicitly in pixels...

Anyway, you must avoid use of Html attributes for styling, and use Css instead ^^

Answer 2

100% is the entire width of the parent. usually the webpage
100 should give you an error...
100px will be exactly 100px.

hope this helps