在工艺指标允许的条件下，为提高浮选机的处理能力，降低药剂耗量，应尽量选用较高的入浮浓度。
参考答案：对
The boy is too young to go to school. [ ]
A. too old to go to school
B. old enough to go to school
C. such young that he can't go to school
D. so young that he can't go to school
心肺复苏时体外心脏按压的正确部位是
A．胸骨左缘心尖部B．胸骨中部C．胸骨中下1/3交界处D．胸骨两侧，锁骨中线第4～5肋间E．剑突下
