单项选择题
The car will be guided by a differential GPS system that corrects errors arising in global positioning satellite signals（）they travel through the ionosphere and troposphere.
A.as B.that C.what D.where
单项选择题 The TTS run will demonstrate （）the car can take curves as fast as a human driver—without driving off a cliff.
单项选择题 It is an early step toward a robo-car that can drive itself, perhaps（）.
单项选择题 On vacation with the family the driver may want to（）and talk to the kids
