影响肺循环血流量的主要因素是（）
A.肺泡气的CO2分压
B.肺泡气的氧分压
C.交感神经
D.迷走神经
E.血管活性物质
参考答案：B
有足球72个，篮球9个，足球的数量是篮球的多少倍？
The mayor of Zhuanghe City was ordered to resign because of his refusal to ________ when more than 1000 villagers got down on their knees before the city government office building, begging for his help.
A．break up
B．link up
C．fill up
D．show up
