You can be ticketed for traveling at an unsafe speed regardless of the speed limit.
No. If the road conditions make it unsafe to travel at that speed, you can be cited for failing to adjust your speed to the road conditions.
Somewhere north of 200mph, which is way unsafe for the road.
Too much or unsafe speed.
Depends on the density of the traffic and the speed limit. If the speed limit is 120kph, then about 35/40 minutes
It all depends on the type of highway and the speed limit signs.
You can only legally travel at or below the posted speed limit, regardless of the high rate of speed of any other vehicle. This follows what moms say to kids: "Just because your friends tell you to do something dangerous or unsafe, it doesn't mean it is okay to do."
criminal such as theft
On many highways it is unsafe to continue at the normal speed limit as you go around a curve (especially for large trucks with a high center of gravity that might tip over), therefor reduced speed signs (often yellow advisory signs not the usual white legal signs) are posted indicating reasonable and safe speeds to use through the curve.
The universal speed limit for material objects is c : the speed of light in a vacuum.
Nothing can exceed the speed of light - Einstein called it the "cosmic speed limit".
Ralph Nader wrote Unsafe at Any Speed.