杠杆传动的主要优点之一是()
A.传动平衡
B.传动比较大
C.精度要求不高
D.结构尺寸小
参考答案:C
David threatened________his neighbour to the police if the damages were not paid.
A.to be reported
B.reporting
C.to report
D.having reported
色相、明度、()为色彩的三要素。
A.光洁度
B.材质质感
C.彩度
D.折射率