In singleplayer, they happen in the campaign pretty often.
In multiplayer, they spawn in the deployments, the carrier, and some spawn points.
Yes there is no doubt about it.
no
Not legally.
No, the BF4 Beta is a separate download/installation.
About 25 pounds.
Now
No, you can be any age to play Battlefield 3.
battlefield 3
Go to multiplayer on the main menu
Dice, a branch of Electronic Arts
It unlocks at 20,000 points
No you can't unfortunately.