【多选题】关于五种运输方式,下列论述正确的有()。
A.
水运是人类最早利用的运输方式之一,具有运量大、运输成本低等特点
B.
航运的特点就是时间短、速度快,但运输成本高,适宜于距离长、要求时间短的运输
E.
与铁路运输 相比 ,管道运输的固定成本比较高,可变成本比较低
【简答题】1) The mechanic(机械师) _____ the plane before it took off. 2) Please _____ words and phrases, not whole sentences. You don’t have time to record exactly what’s said. 3) Keep the onions _____ from the b...
【简答题】设 A , B , C 构成一个随机试验的样本空间的一个完备事件组,且P(A)=0.5,P(B-)=0.7, 则 P(C)= ,P(AB)=
【简答题】What does the comment refer to? Write the appropriate word or phrase: 7. If we don’t produce and sell more than 10,000 sets a year, we won’t make any (p)_____________ .
【单选题】( )7. Don’t make any noise while the students _______ to the teacher.
【单选题】设 构成一完备事件组,且 , , , , ,则 【 】。
【简答题】There’re health and safety rules to keep you and other people safe. You all have a legal duty to behave ___1____ a safe way. Keep very clean. ___2___ your hands thoroughly after you go to the toilet, ...
【单选题】设 构成一完备事件组,且 , ,则概率 ( )。
【单选题】设 构成一完备事件组,且 , ,则 ( ) 。