若有10道选择题,每题有A,B,C,D四个答案,只有一个正确答案,求随机作答恰好答对4道的概率为()。
Goods are carried by several of transport--on road or rail, by sea or air.
You can _____ some bottles of wine, or some chocolates, or a bunch of flowers.
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
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