Interview in ESA

Hi, I recently was interviewed for a s/w engineer post in ESA. I was asked the following question. "Suppose you're hired, what would you do on your first day at work ?". Although, I answered it, I was not fully satisfied with my answer. Has anyone any hint on this?
The same question I was asked when I was interviewed for a National Expert post at EUROSTAT.
Thanks and any advice would be invaluable.

you can reply that you will check out the informative links and helps that are provided by the company, say training links, timesheets etc.
Meet your new team members, get well acquainted with the new building or location. Mee t your managers etc