The speed limit is the top speed that is legally allowed. If it is exceeded, you are breaking the law.
If the speed limit is 50, drive 50. If the speed limit is 60, drive 60 and so on.
If it's not the speed limit yes
You can drive what ever speed you want but if you are over the limit, you may be arrested.
None. The speed limit is the limit. If you drive above it you are breaking the law. Simple, really.
AUTOBARN, Germany
Yes. You just have to drive the speed limit and obey all the rules of the road as not to get in trouble with the police. If you aviod any confrentation with Police Officers you can drive anywhere.
It depends on the speed that you drive at which, in turn, depends on the speed limit, road conditios, your vehicle, traffic etc. At 20 mph (the speed limit on my street) 5 hours. On a UK motorway, 1.43 hours or just over 1 hour 25 minutes. On roads without speed limit, less than that.
No. You are also allowed to drive at speeds below the speed limit. Some highways will post a minimum speed in addition to the speed limit, with the requirement that you use four-way flashers if your speed drops below the posted minimum.
Yes it does have one so you couldn't drive the speed you wanna drive.
Always
Whatever the speed limit is.