已知数列{an}的首项a1=2,且an+1=2an+1,(n≥1,n∈N+),则a5=( )
A:7
B:15
C:30
D:47
推理是化学学习中常用的思维方法.以下推理不正确的是( )
以下对应关系搭配恰当的一组是( )
— You are wanted on the phone. — __________ nobody knows I'm here.
Can I have some sweets?
No, ____ ____.