下列运算中，计算正确的是（ ）
A：2a•3a=6a
B：（3a2）3=27a6
C：a4÷a2=2a
D：（a+b）2=a2+ab+b2
阅读短文，下列问题
B
Amy
I like singing. I can play the guitar and the piano. I want to join the music club.
Bill
Do you want to know my favorite sport? I like playing basketball very much.
I can playing it well.
Jackie
I like playing the piano very much. I often play the piano after school.
Frank
My favorite sport is playing soccer, and I’m good at it.
对下列句中文言句式的判断，正确的一项是（ ）①吾属今为之虏矣 ②燕国见陵之耻除矣 ③竖子不足与谋 ④何厌之有
下列关于克隆的叙述错误的是（ ）
已知定义在R上的可导函数y=f（x）的导函数为f′（x），满足f′（x）＜f（x）且y=f（x+1）为偶函数，f（2）=1，则不等式f（x）＜ex的解集为____
