施工招标项目工期超过( )的,招标文件中可以规定工程造价指数体系、价格调整因素和调整方法。
A.三个月 B.六个月C.九个月 D.十二个月
参考答案:D
A yellow signal floating in the air from a small parachute,about 300 feet above the water,would indicate that a submarine().
A.has fired a torpedo during a drill
B.is about to rise to periscope depth
C.is on the bottom in distress
D.is disabled and unable to surface
焊接前,应根据焊件的(),选择适当的焊炬及焊嘴。
A、材质
B、形式
C、大小
D、厚度