In order to maintain the safety of drivers, the individual states can determine the speed limits depending on the quality of local roads.
the state with the highest speed limit is Texas
There is no state in which you can legally drive over the legal speed limit. Yup, there is no state where it is legal to do illegal things. However, there are some states that have higher speed limits than others. I believe that Pennsylvania still has a 55 mph speed limit, where Florida has some stretches of highway where 75 mph is the legal limit. At one time, Montana had (and may still have -- you may want to check) a stretch of highway that has no legally set speed limit. However, there is a difference between driving over the limit and having no limit. So in answer to your question: There is no state that has a law that says you can legally break the law.
Alaska
The default speed limit on New York state highways where no speed limit is posted is 55 mph.
Yes, many state highways have a minimum speed limit.
Most states don't have truck speed limits. So in a state like Colorado, New Mexico, Arizona, etc. (where the speed limit is 75), trucks can do the speed limit.
A slow speed limit cannot be enforced on a private road in the state of Virginia. You can put a sign up but is will not be enforced by the state.
The speed limit for boating on Ohio state park lakes between sunset and sunrise is 10 mph. It is important to adhere to this speed limit to ensure safety on the water, especially during low-light conditions.
There is a stretch of Texas state route 130 north of San Antonio with a posted speed limit of 85 mph (137 kph).
This is defined by state law. It is usually somewhere near 25-35 MPH, but you'd need to check the specific state's laws to be sure.
Speed LIMIT means exactly that. That is the fastest speed you are allowed to travel under perfect road conditions. No state allows you to exceed the speed limit to pass another vehicle.
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