地球表面约有（）以上被水所覆盖
A.20%
B.30%
C.50%
D.70%
参考答案：D
函数y=ln（1-2x）的定义域是 ______．
Congratulations! It seemed that our boss was __________ with your work today.[ ]
A. dishonest
B. confused
C. satisfied
D. disturbed
