【简答题】Two vectors are defined to be equal if they have the same magnitude and the same dirction. Graphically, this means that they have the same length and are parallel to each other.A consequence of the de...
【简答题】阅读理解。 Hotlines have become common in China. Some radio broadcasting stations use hotlines to encourage the listeners to take part in the talk shows. That's a good idea. Yet, the fact is some people do...