成人不存在造血的红髓骨组织的是()
A.脊椎骨
B.肋骨和胸骨
C.股骨的骨干
D.髂骨
E.颅骨
参考答案:C
Mrs. Smith found the toys here and there, so she asked her son to ______ his toys before having dinner [ ]
A. put off
B. give away
C. put away
D. give out
芳磺酸盐的碱熔是工业制备酚类的重要方法,对其说法正确的是()。
A.该方法工艺简单,适用于多种酚类的制备
B.反应一般在高温下进行
C.该方法常用苛性钠或苛性钾做碱熔剂
D.该方法工艺先进,几乎不产生废液