为使纵拉杆在受到各向冲击力时都有一个弹簧起缓冲作用,两端的弹簧装在球头销的()。
A. 两侧
B. 同一侧
C. 内侧
D. 外侧
()behalfofmyowners,Igiveyoumyformalnotice.
At
B. On
C. Of
D. In
()anumberofhome-madenauticalinstrumentsandforeign-mademetersonthebridge.
A. Have
B. Has
C. Thereis
D. Thereare
()asthechemicalextinguisheragent,shouldbeusedforaanelectricfire.
A. Drychemicalorfoam
B. Foamorsodaacid
C. carbondioxideorfoam
D. carbondioxideordrychemical