如果考虑经济性,一般以采用()为最合理。
A.弹簧钢
B.铍青铜
C.磷青铜
D.冷轧不锈钢
参考答案:A
-Why did John ask me about the problem?
-________,he tried to find a better way to settle it.
[ ]
A.Not to be satisfied
B.Not satisfied
C.Not being satisfied
D.Don't satisfy
根据《工业企业设计卫生标准》,每个工作日接触噪声时间为4小时,其允许噪声标准是()
A、85分贝
B、88分贝
C、91分贝