Rhonda asks: I work at Fallingwater. Why does it seem like the only time you can hear the train whistle is when it is going to rain? So, we have a couple of clues: You hear a train and then it rains.

Imagine traveling from New York to Los Angeles in less than an hour or from London to Paris in 15 minutes. Sounds impossible, right? Well, not for China’s biggest missile manufacturer, which claims to ...