已知Ｂ点高程为241.000m，Ａ、Ｂ点间的高差hAB=+1.000m，则Ａ点高程为240m．
参考答案：错
张骞两次出使西域：
No matter how frequently ， the works of Beethoven still attract people all over the world. [ ]
A. performed
B. performing
C. to be performed
D. being performed
