Twitter usage survey - just 5 questions

I want to work out the best time to get a tweet noticed. You can help by answering JUST FIVE questions.

Two are about reading tweets, two are about when you send yours. Please ignore @replies that you send when answering the question about sending tweets.

Results will be published at malcolmcoles.co.uk. Thanks for taking part.

Q1 How many tweets do you read when you look at Twitter - ie how far back in time do you look? (There are 20 at a time on a web page)

I read everything tweeted since I last looked at Twitter
Other:

Any other info or advice? If you have any tips, pointers, useful URLs etc, let me know! Leave your Twitter name if you'd like to be thanked when results published and notified of them.