BlackBerry Calendar : Some questions

Hi guys,

Sorry to bother but I searched and can't seem to find any answer that deal with the questions below. Can someone enlighten me? Thanks.

1. What is the real purpose of the option "Show Time As" when creating new appointment entries in BlackBerry calendar?

What is the effect if I choose free or tentative or busy or out of office?

2. Is there way to hide calendar entries from Agenda view. E.g. I set up a lot of birthday entries and do not want them displayed and clogged up the Agenda view screen.

or can I choose and hide calendar entries belonging to a calendar account?