n个人随机地排成一列，其中甲和乙排在一起的概率是_____。
设事件A,B，则P(A-B)=( )
对随机事件A和B，下述关系中正确的是：
10个人随机的围绕圆桌而坐，其中甲和乙围坐在一起的概率是_____。
10张奖券中只有一张中奖，现有10人排队依次抽奖，每人抽一张，取后不放回，则下列说法正确的是_____。
一袋中有50个球，其中20个红球，30个白球。今有两人从中各取一球，取后不放回，则第二个人取到红球的概率是_____。
甲乙射击一个目标，甲命中的概率是0.6，乙命中的概率是0.9，两人同时各射击一次，目标被命中的概率是______。
单词 magnetorheological 的意思是 ( )。
A ( ) is an integral material to satisfy the user requirements, which are not attainable by the individual constituents.
“impact strength”意思是 ( )。
Landfilling is the（ ）desirable method of dealing with municipal solid waste.
( ) means converting waste materials into new materials and objects to save energy and lower greenhouse gas emissions.
Multi-layer antireflective coatings deposited by sol-gel methods have been demonstrated ( ) many substrates including glass.
UHPC exhibits excellent rheological behaviors, improved in mechanical and ( ) performance with very high compressive strength, and non-brittleness behavior.
单词 homogeneity 的反义词是 ( )。
