部分中空铝型材的中空空腔内部贴有()材料以达到隔音减振的目的。
A.防振
B.金属
C.复合
D.聚酯
参考答案:A
Please tell the students ________ too much noise in class. [ ]
A. to make
B. to take
C. not to take
D. not to make
T68镗床主轴机构中钢套与主轴的配合间隙为()。
A.0.005~0.01mm
B.0.015~0.02mm
C.0.02~0.03mm
D.0.05~0.1mm