若频率增大,波长将() A.减少 B.增大 C.增加10倍 D.不变 E.以上均不是 发布时间:2017-08-24 11:17 │ 来源:www.tikuol.com 题型:单项选择题 问题: 若频率增大,波长将()A.减少B.增大C.增加10倍D.不变E.以上均不是
题型:单项选择题 There was a fire in the street last night, but the firemen _______within twenty minutes. [ ]A. took it out B. brought it out C. worked it out D. put it out 查看答案
题型:单项选择题 某固体物质的摩尔质量为M,密度为ρ,阿伏伽德罗常数为NA,则每个分子的质量和单位体积所含的分子数分别为( )A.NA/M,NAρ/MB.M/NA,MNA/ρC.NA/M,M/NAρD.M/NA,NAρ/M 查看答案