题目

In the USA, driving laws differ somewhat from state to state and considerably from what you are used to. Here is a list of some important differences. Speed Limits Speed limits are designated in miles per hour(MPH),not kilometers. One mile equals 1.6093 kilometers. Within cities the speed limit is usually 25 mph. Major streets with two or more lines may post a higher limit of 35 mph, but you should assume a 25 mph limit unless you see a sign with a higher limit. Highways have a speed limit of 55 mph, with some interstate highways posting a higher limit of 65 mph. Fines for speeding are he14．蛔虫病是一种常见的（　　）传染病．A．呼吸道B．消化道C．血液D．体表