围术期一旦发生返流和误吸，其结果取决于。（）

A.误吸物的量

B.pH值

C.误吸物的性质（血液、固体等）

D.发生的时间

E.麻醉药的种类

— __________ is it from Sunshine Town to the center of Beijing?

— It’s about 20 kilometers ________ our school.

A．How far, far from

B．How long, away from

C．How far, far away from

D．How far, away from