画正等轴测图时，三个轴的轴向缩短宰为了作图方便，轴向缩短率都为（）。
A.0.50
B.0.82
C.0.85
D.0.90
参考答案：B
货币在执行价值尺度职能时是 （ ）
A．价值不变的特殊商品
B．想象的货币
C．现实的货币
D．一种价值符号
________ we stood at the top of the building, we were able to enjoy the town below clearly.[ ]
A. As
B. Although
C. Unless
D. Until
