How to enable Trip Computer (MPG) and parking sensor?

Guys, three questions:
 
a) I see lots of information on the display on the front panel of my Audi. I clicked a "reset" buttom and I see "Trip information" checked for miles per gallon (MPG) information. However, I can't see how many miles per gallon I am getting there. I see lots of information such as "Temperature", "MPH", "figure showing when I open a door". What do I need to do in order to visualize the MPG information? In the list of features presented by the dealer, "trip computer" was included.
 
b) Reading my manual, they talk about "parking sensor". How do I know if my vehicle is equiped with that? I already attempted to park near an object and I heard no signal. I am just wondering if that is something I should enabled, in case my vehicle is equipped with that rear parking sensor.
 
c) Finally, if I want to find a list of all options included in my car, how can I do that? Is Audi able to give me that information if I provide the VIN number?

re: (a)
the rocker switch on the end of tour wiper lever should let you scroll through the trip information
re: (b)
if you have a series of round "dots" on your rear bumper you may very well have the rear parking sensor.
re: (c)
VIN Codes can't always tell you all of your options, however go to these sites to learn more, and to enter your VIN.
http://www.autoinsurancetips.com/decoding-your-vin
and
http://www.analogx.com/contents/vinview.htm
and
http://www.angelfire.com/ca/TORONTO/VIN/VINcode.html

Depending what package came with your car:
2006: technology package(bi-xenon, color trip display(displays mpg), memory seats, bluetooth), for 2007, it was called Convenience package. If you don't have this package, then it will only display "miles to empty" info
The parking sensor I believe was an option on its on