在“探究单摆周期与摆长的关系”的实验中，提供的器材有：铁架台、铁夹、细线、有孔的小铁球、秒表、刻度尺，还需补充的器材是[ ]
A、
B、
C、
D、
答案：D
— Has the homework been finished?
— Our teacher asked you .
A．whether had the work been finished
B．if the work had been finished
C．the homework has been finished
D．the work had been finished
有些史学家认为，“太平天国的改革方案包含了很多激进的特征.对不满的民众很有吸引力。其方案中对民众最具有吸引力的是（）
A.平均分配土地
B.发展工商业
C.建立民主政治
D.兴办学校教育
