The engine is started with() supplied from air receivers.
A. pressure Oil
B. pressure water
C. compressed air
健身健美操一套时间为______,竞技健美操一套时间为______.
猪棘头虫属于()
A. 外寄生
B. 多宿主寄生虫
C. 暂时性寄生虫
D. 单宿主寄生虫
E. 专一宿主寄生虫
采用佛尔哈德法测定水产罐头的氯化钠含量前,称取约20g样品,精确至()。
A. 0.01g
B. 0.1g
C. 0.001g
D. 0.000lg