有介绍汽车的英语文章吗？

-- Scott Perl, Albuquerque, N.M.

A: Auto racers have told us the main advantage in filling tires with nitrogen instead of ambient air is that nitrogen tends to maintain more consistent tire pressure over a wide range of temperatures. As friction between the tire and pavement drives up the temperature, air with varying amounts of moisture content responds differently and can cause inconsistencies in tire pressure. While racing drivers are more likely to notice the advantages of nitrogen than everyday drivers, we haven't heard of any disadvantages to using it.

Skeptics question the practice, noting that ambient air is about 80% nitrogen and that it expands and contracts at the same rate as pure nitrogen. A number of readers say there's no appreciable difference in how the tires will react if filled with nitrogen, especially in everyday use.

Q: Is it safe to use cruise control in rain or on wet pavement?

-- Scott Brake, Westminster, C