光的吸收定律即朗伯-比尔定律,是分光光度法中定量的依据。
参考答案:对
一家书店前3个月售出图书的数量分别是507本、516本、496本,这家书店一年大约售出图书多少本?
根据所给词,将下列词分类,并在每一行的最后一格内再填一个相关词。
practice, sentence, cassette, comma, write, TV, video, frustrated,
grammar, speak, CD, learn, excited, pronunciation, ashamed, embarrassed
1. TV
2. speak
3. sentence
4. frustrated