关于遗传代谢缺陷病,正确的说法是()
A.对脑发育、功能影响小
B.多基因遗传病
C.较少见,对机体损害小
D.线粒体遗传病
E.国内已开展血红蛋白病、有机酸尿症的高危筛查
参考答案:E
During her childhood Susan read a lot about Chinese history, from which she _________ greatly in her work in China now.
A.observes
B.recovers
C.recognises
D.benefits
采用切削叶轮调节时,对于中、高比转数水泵,根据第二切削定律,调节后功率与原功率的比为切削比的()。
A.一次方
B.二次方
C.三次方
D.不变化