This would depend upon where the designated traffic lane is located at. They could be on a State Highway, a City Street or Alleyway, in a Parking Lot, or a number of other locations somewhere.
Any one of the locations mentioned above have "designated traffic lanes" and the speed limits vary greatly between these different locations. The presence of certain pedestrians can also change the speed limit as well, such as in a school or hospital zone.
Many Highways throughout the United States have speed limits posted anywhere from 45 MPH to 70 MPH. A City Street or Alleyway can have posted speed limits ranging from 15 MPH to 45 MPH. A Parking Lot can have a posted speed limit of 5 MPH to 10 MPH. All these different locations have "designated traffic lanes".
15 mph
15 mph
15 mph
15 mph
15 mph
15 miles per hour
15 mph
15 mph
If you have an acceleration lane you should accelerate to the flow of traffic and merge into traffic.
No traffic, the posted speed limit. Non-posted 2-lane highways are default 55mph. In traffic, only as fast as safe, no tailgating
Drivers intending to stay on the highway/freeway should stay in the right lane or the lane designated as a through-lane. The only times you should move left is to allow vehicles to merge from a right side on ramp (and move back to the right lane as soon as you can), or to pass slower traffic already in the right lane (then move back to the right lane when it is safe to do so). If a freeway provides a "slower" lane and you drive slower than the maximum speed allowed, you should use the slower lane. But never hog the passing lane just to keep driving in it; move over and let faster traffic pass you.
They are as high as 65. In North Dakota, the speed limit is 65 mph on two-lane highways if posted for that speed.