[originaltext] (1) The US Justice Department is suing the German carmaker Vo

(1) The US Justice Department is suing the German carmaker Volkswagen which has admitted fitting emission cheating software to millions of vehicles. The lawsuit accused VW of causing excessive pollution harming public health and cheating consumers. "The civil complaint is the latest episode in the scandal that is threatened to engulf what was the world’s largest automaker until last year when the cheating allegations emerged. The Environmental Protection Agency says thousands of tons of excess nitrogen oxide were emitted from Volkswagen diesel cars as a result of software that activated pollution controls only when the vehicles were being tested. (2) The lawsuit covers around half a million cars, but VW has admitted installing the devices on 11 million. "
1. What is the Volkswagen?
2. How many cars are covered by the lawsuit?