【单选题】青少年膳食总原则为充足的能量足量的动物性食品.果蔬.谷类及( )。
【单选题】平面定轴轮系中,当外啮合齿轮的对数为偶数时,表示轮系首、末轮转向( )。A. 相同 B. 相反C. 同时指向节点 D. 同时背离节点
【单选题】It is not expected ____ he said caused so much discussion at the meeting.
【简答题】What caused a change in the author’s understanding of keeping a diary? A.A dull night on the journey. B.The beauty of the great valley. C.A striking quotation from a book. D.Her concerns for future ge...
【单选题】According to the writer, what is the worst thing caused by high young child mortality?
A.
The suffering children are subjected to.
B.
Inaccurate and unreliable data on child mortality.
C.
The large-scale waste of human potential.
D.
The lack of labor force for economic development.
【简答题】What caused the giant tsunami?