在低合金钢焊缝金属中，如冷却速度过慢，容易形成（）组织。
参考答案：珠光体
_______ advantages and disadvantages, Mr. Smith decided to leave the company and go to the west to try his fortune.
A．Having compared
B．Having balanced
C．Having observed
D．Having examined
提示肺癌患者肺功能检查异常的是（）
A.FEV1%为83%
B.MVV%为72%
C.MMEF为3L/s
D.VR为95%
E.血气分析PaO2为10.8kPa
