焊接后金属产生裂纹的可能性与金属本身的化学成分和（）有关。
A.形状
B.厚度
C.性能
D.温度
参考答案：C
The parents suggested _____ in the hotel room but their kids were anxious to camp out during the trip.[ ]
A. sleep
B. to sleep
C. sleeping
D. having slept
简述ERP中采购管理的业务内容有哪些？
