小明为深入了解唐太宗,进行了探究性学习。下列可以为他提供有效信息的文献是
A.A
B.B
C.C
D.D
答案:C
we had to walk home.
A.There ere no boxed in the streets
B.Being no buses on the streets
C.It was not a bus
D.There being no buses in the streets.
百分表架是专门用来夹持百分表的,通常有()几种形式。
A.轨道座式
B.机械式
C.磁力座软轴式
D.磁力座式