第16题: [单项选择]FITC的最大吸收光谱和最大发射光谱的组合中,正确的是() A. 490~495nm,520~530nm B. 570nm,595~600nm C. 550nm,620nm D. 340nm,613nm E. 360nm,450nm 参考答案:A
第17题: [单项选择]According to the author, the first computing machine was in use ______ years ago. A. 500 B. 1,000 C. 5,000 D. 10,000 参考答案:C 答案解析:[分析] 细节明示题。第一段第三行写道:The first computing machine,in use more than 5,000 years ago,was the fingers and