至2009年末,杭州市参加基本养老保险约有3 422 000人,用科学记数法表示应为______人.
3 422 000人=3.422×106人.
It's six now. Lanlan _____ up, but she often _____ up at half past six.[ ]
A. gets, is get
B. gets, is getting
C. is getting, gets
D. gets, gets
期权定价中,通常使用标的物价格的标准差代表波动率。