After completing and signing it, please return the form to us in the envelope provided.填完表格并签名后，请装进所提供的信封里寄还给我们。Are you sure you entirely apprehend the importance of completing these forms as accurately as possible?你肯定你完...
乙烯和反式二氯乙烯在红外光谱的这个区域都无活性.Ethylene and trans - dichloroethylene are both inactive in the infra - red in this region.光谱的原色是红 、 绿、蓝.The primary colors of the spectrum are red, green and blue.原子光谱的研究能给出原子能级信息.Investigation of...