代理业务应贯彻（）的原则。
A、先收后付
B、先存后支
C、不予垫款
D、收妥抵用
参考答案：A, B, C
But the unpleasant feeling of coldness disappeared at the _______ of his students pouring out of their
classroom to give him a warm, wordless welcome.[ ]
A. sight
B. scene
C. view
D. sign
不宜做硬膜外麻醉的是（）
A.高血压、心脏病
B.低血容量休克
C.椎管内转移癌
D.妊娠高血压症
E.出凝血机制障碍
