png的最优值是（） A: -2 B: -6 C: -45/4 D: -7

为鉴定经纬仪的精度，对已知精确测定的水平角（α=45°00′00.0″）作n次观测，结果为45°00′06″，44°59′55″，44°59′58″，45°00′04″，45°0′03″,45°0′04″,45°0′00″,44°59′58″,44°59′59″,44°59′59″,45°00′06″,45°00′03″。设α没有误差，试求观测值的中误差。

为了鉴定经纬仪的精度,对已知精确测定的水平角a=45。00’00”做了12次观测,结果为:45。00’06”44。59’55”44。59’58”45。00’04”45。00’03”45。00’04”45。00’00”44。59’58”44。59’59”44。59’59”45。00’06”45。00’03”设a没有误差,试求观测值的中误差。

为鉴定经纬仪的精度，对已知精确测定的水平角（α=45°00′00.0″, 认为 没有误差）作12次观测，结果为45°00′06″，44°59′55″，44°59′58″，45°00′04″，45°0′03″，45°0′04″,45°0′00″，44°59′58″，44°59′59″，44°59′59″，45°00′06″，,45°00′03″。据此计算观测值的中误差为（）。 A: ±1.2″ B: ±3.1″ C: ±3.6″ D: ±3.8″

45的59是______，45又是______的59．

12号道岔的辙叉角是。。 A: 1◦59’57” B: 4◦45’49” C: 6◦20’25” D: 3◦10’47”

以下图像文件格式中，(59)不支持真彩色图像。 A: PCX B: PNG C: TGA D: EPS

9*1=9 9*2=18 9*3=27 9*4=36 9*5=45 9*6=54 9*7=63 9*8=72 9*9=81

执行下列代码<img src="data:image/png;base64,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" />后，Y的值是？ （ ） A: 9 B: 一维数组{-21, -18, -15, -12, -9, -6, -3, 0, 3, 6, 9} C: 一维数组{-21, -18, -15, -12, -9, -6, -3, 0, 3, 6} D: 6

列竖式计算下面各题6t÷7=16÷下=60÷7=59÷6=下8÷9=5下÷7=