HTML5 and Android development tools

I am new Android developer and want to learn it.
I have some questions:
1) I want to use Eclipse as a tool. Do I still need to learn HTML5?
2) What is relationship between Eclipse and HTML5?
3) My goal is develop applications to run in Xoom (Android tablet) to connect our company's SQL server data.
Can I use HTML5 to do it?

asp fun wrote:1) I want to use Eclipse as a tool. Do I still need to learn HTML5?

Of course you do. Why wouldn't you?

asp fun wrote:2) What is relationship between Eclipse and HTML5?

Eclipse is an editor. HTML5 is a markup language.

asp fun wrote:3) My goal is develop applications to run in Xoom (Android tablet) to connect our company's SQL server data.
Can I use HTML5 to do it?

You could if you use Javascript and optionally AJAX capabilities (depending on your needs) that communicate with a servlet on your company's server.

Thank you, Koen Aerts.
As I understood that if I only use HTML5 to develop, I need to use Javascripts in HTML5.
But how to load app into Xoom as Eclipse will compile a apk file?

Well, are you making a native app or a web app? Both are different things. The web app will be accessible via the browser. On iPhones you can create stand-alone HTML5 apps that looks like native apps; I don't know if the same is possible on a Xoom.