拱涵采用片石回填时,其施工方法有()。
A.分层填筑法和片石套拱法
B.片石套拱法和竖向填筑法
C.分层填筑法和竖向填筑法
D.混合填筑法与片石套拱法
参考答案:A
.He is a student at Oxford University,_______for a degree in computer science.
A.studied
B.studying
C.to have studied
D.to be studying
血平板上菌落的溶血现象,不包括()
A.α溶血
B.β溶血
C.ζ溶血
D.γ溶血
E.双环