the only state, along with the District of Columbia, that prohibits the use of radar detectors. Wake Island The speed limit on Wake Island is . Washington The Revised Code of Washington permits speed limits of in sections deemed appropriate by an engineering study. As of February 2016, the typical speed limit on a Washington freeway is rural, urban (the speed limits on these types of freeways only vary in the Tri Cities), with a truck speed limit no higher than 60 mph. The posted truck speed limit does not apply to any auto stage towing a trailer or trucks less than 10,000 pounds gross weight. Limits were raised to current speeds following the elimination of the federal 55 mph speed limit, to more closely reflect the common speeds of traffic at that time. There are a wide range of speed limits statewide, due to legislated flexibility for WSDOT in balancing the desire for transportation speed against safety considerations for any particular stretch of highway. The default speed limit on a rural 2-lane highway in Washington is ; however, the limit on undivided highways varies. In mountainous country like the Cascades and Olympic Mountains, certain twisty roads are limited to , whereas some flat, straight highways in eastern Washington have a limit of 65. The speed limit for motorhomes and autos with trailers is 60 mph, the same limit as trucks. Roads with traffic lights are limited to 55 mph. The school zone speed limit is but is in effect during certain hours or if children are present. Divided highways in Washington are rare, however, U.S. Route 395 between Pasco and Ritzville is a high-speed divided highway with a maximum speed limit of . Some areas within Washington State use variable speed limits such as on portions of I-90 between Seattle and Issaquah and over Snoqualmie Pass. West Virginia The speed limit on most rural Interstates is . Urban Interstate speed limits generally vary from to . Sections of I-64 and I-68 have lower truck speed limits because of steep grades; otherwise, West Virginia does not post separate truck speed limits. The West Virginia Turnpike between Chelyan and Mahan, and I-77 between Princeton and Bluefield has a 60 mph speed limit because of sharp curves. Speed limits on 4-lane divided highways are normally , although some stretches within cities are posted as low as . Open country highways have a