单项选择题 The car will be guided by a differential GPS system that corrects errors（）in global positioning satellite signals.

单项选择题 However, since methanol-fueled vehicles could be designed to be much more（）than gasoline clone vehicles fueled with methanol, they would need comparatively less fuel.

单项选择题 Methanol’s most attractive feature is that it can reduce（）about 90 percent the vehicle emissions.