《中华人民共和国献血法》中规定,献血者每次采血量最多不得超过()。
A.200ml
B.300ml
C.400ml
D.500ml
E.600ml
参考答案:C
Sarch ________ curly blond hair when she was a child. [ ]
A. is
B. have
C. had
D. having
给煤机在运行中发生卡、堵时,禁止()直接拨堵塞的煤。如必须用手直接工作,应将给煤机停下,并做好()的措施。