Ariel connections what will I find on a standard mast?

Ok looking at dab and thinking about changing the standard ariel. What connections will I find under the roof lining? The double blue connection in the dash I presume goes to the ariel base and this is not amplified? Does this cable have a connection near the base or is it one length?

If I was to buy a dab/fm/am ariel with short connections would I need to buy just a dab extension cable and use the existing fm cable?

Is the standard ariel aplified if so is there a power and earth cable under there also?

Thanks in advance ady