Directions:For each blank in the following passage there are four words or phrases marked A,B,C and D. Fill in each blank with the word or phrase that best fits the context. One day, at a restaura
现有反应:4A+3B4C+2D,其反应速率可以分别用vA、vB、vC、vd(mol·L-1·s-1)表示,则其反应速率正确关系是
从下列文字信息看,新中国成立后,旨在变革土地所有制的措施是( ) A.人民公社好 B.把大跃进战鼓敲得更响
设f(z)=,z1=3+4i,z2=-2-i,则f(z1-z2)是( )A.1-3i B.-2+11i C.-2+i D.5-5i
已知f(x)=(x∈R且x≠-1),+2(x∈R). (1)求f(2),g(2)的值; (2)求f(g(2))的值; (3)求f(g(x)).
将正面分别标有数字1、2、3、4、6,背面花色相同的五张卡片沅匀后,背面朝上放在桌面上,从中随机抽取两张。 ⑴写出所有机会均等的结果,并求抽
You wake up in the morning,the day is beautiful and the plans for the day are what you have been looking forward to for a long time.Then the telephone rings,you say hello, and the drama starts
阅读理解 阅读理解下面的短文,然后按要求答题。 There are twelve months in a year. The names of the twelve months are January, February, March, April, may, June, July, August, Sep