流体中任何一点上静压与动压的（）称为全压。
A、代数和
B、代数差
C、代数积
D、代数商
参考答案：A
It is an abundance of cheap goods and quick delivery service ______ account for the fact that the
number of Internet shopping on this website is four times ______ it was last year.[ ]
A. that; that
B. which; what
C. what; that
D. that; what
从事生产经营的纳税人，自领取营业执照之日起( )内，持有关证件，向税务机关申报办理税务登记。
A．15日
B．30日
C．45日
D．60日
