After 8 to 12 days, on average, symptoms of measles can begin. The period between measles transmission and the start of symptoms is called the incubation period.
Driving Laws In Greater Philadelphia. The maximum speed limit in Pennsylvania is 55 miles per hour unless posted otherwise. The maximum speed limit on interstate highways is posted after each interchange; on other highways the maximum speed limit is posted at approximately half-mile intervals.
Pennsylvania has a 4-feet passing law. In 19 other states there are general laws that provide that motorists must pass at a âsafe distance.â These laws typically state that vehicles must pass bicyclists at a safe distance and speed, but usually are not more specific.