【单项选择题】
如右下图所示,OC=60.500m,β(∠AOC<sub>0</sub>)-β<sub>1</sub>(∠AOC) =+30″,则CC<sub>0</sub>的值为()<br /> <img src="https://img.ppkao.com/2019-05/liuye/2019050910441434529.jpg" /><p> 如右下图所示,OC=60.500m,β(∠AOC<sub>0</sub>)-β<sub>1</sub>(∠AOC) =+30″,则CC<sub>0</sub>的值为()<br /> <img src="https://img.ppkao.com/2019-05/liuye/2019050910441434529.jpg" /></p>
A、A.+0.009m
B、B.–0.009m
C、C.–0.0045m
D、D.+0.0045m