A.1/3000 B.1/3500 C.1/4000 D.1/5000
A.前-后-后-前 B.后-前-前-后 C.后-后-前-前 D.前-前-后-后
A.91°45′24″ B.268°14′36″ C.148°17′00″ D.91°14′36″