一列简谐横波在 t = 时的波形图如图( a)所示, P、Q是介质中的两个质点,图( b)是质点 Q的振动 图像。
求 (i )波速及波的传播方向; (ii )质点 Q的平衡位置的 x 坐标。
暂无解析
Weshallbegladtoreceiveyouoffer ___walnutmeat,shipment,____September/October;_____transshipmentatHongkong.
翻译:Wewouldliketoinformyouthatatpresentwecansupplyyouwithvariouskindsofmen'sleathershoes.
You’llbetheretomorrow--youwon’t________me________,willyou?
_______thefirstlanguageisusedintheteachingofthesecondlanguageintheGrammar-TranslationMethod.
翻译:fyoumakeusanofferatcompetitivepriceswecansellalargequantityofchemicalproductinourdistrict.