a)
http://w3techs.com/technologies/deta...-flash/all/all
b) Flash is used by 14.2% of all the websites.
Popular sites using Flash
Google.com
Youtube.com
Yahoo.com
Bbc.co.uk
People.com.cn
Adobe.com
Flickr.com
Dailymotion.com
Rakuten.co.jp
Amazon.co.uk