A:7
B:8
C:9
D:10
-- What is Nancy doing now?
-- She, with her parents, some shopping.
用一把刻度尺测量某物体的长度,记录到的数据是5.72cm,则准确值是 ____cm,估读值是 ____cm,所用的刻度尺的分度值是 ____cm.
观察下列数据: 23 , −39 , 427 , −581 …则第n个数为____.