如图4-5所示,某测量小组将经纬仪安置在P点,用方向观测法观测水平角,观测值如表4-5所示,请试着完成表中需要计算的内容。
参考答案:
分析如下(见表4-11)。
While he was in Beijing, he spent all his time ______ some important museums and buildings.
A.visiting
B.traveling
C.watching
D.touring
轴承装配时,为什么必须先擦净辊颈再抹润滑油?