不锈钢弹簧管的允许测量范围是( )。
A．0.06～16MPa
B．0.1～6MPa
C．16～60MPa
D．0.1～6MPa
参考答案：D
在宏定义#define PI 3.14159中，用宏名PI代替一个______。
Cancellation of the flight ______ many passengers to spend the night at the airport.
A．resulted
B．obliged
C．demanded
D．recommended
