某学生在实验报告中有以下实验数据：①用托盘天平称取11.7克食盐；②用量筒量取5.26毫升盐酸；③用广泛pH试纸测得溶液的pH值是3.5；④滴定未知浓度的盐酸用去23.10毫升NaOH溶液．你认为数据合理的是（ ）．
某学生在实验报告中有以下实验数据：①用托盘天平称取11.7克食盐；②用量筒量取5.26毫升盐酸；③用广泛pH试纸测得溶液的pH值是3.5；④滴定未知浓度的盐酸用去23.10毫升NaOH溶液．你认为数据合理的是（ ）．
精确
用准确称量的NaCl配制1mol·L－1标准溶液，应选用的一组仪器是（ ）．
用准确称量的NaCl配制1mol·L－1标准溶液，应选用的一组仪器是（ ）．
如果用一把最小刻度是毫米的刻度尺量出某物理量的长度是764.5毫米，则这里的有效数字是____位，数值中的数字____是估计出来的，是不可靠数字．
如果用一把最小刻度是毫米的刻度尺量出某物理量的长度是764.5毫米，则这里的有效数字是\_\_\_\_位，数值中的数字\_\_\_\_是估计出来的，是不可靠数字．
Practice 9 Generally, however, modern examinations are, written. (1) The written examination, where all students are tested on the same question, was probably not known until the nineteenth century. Perhaps it came into existence with the great increase
Practice 9 Generally, however, modern examinations are, written. (1) The written examination, where all students are tested on the same question, was probably not known until the nineteenth century.
His decision was _____, since he could not see the action from where he was standing.
His decision was \_\_\_\__, since he could not see the action from where he was standing.
In this book the writer gives us a(n) _____ picture of social history.
In this book the writer gives us a(n) \_\_\_\__ picture of social history.
