【单选题】按 Windows 键 +D 的作用是( )
【单选题】听力原文:M: Mary' would you like to be my cooperation partner next time? W: Sure. I just can't believe you still want to work with me after I messed up last time. Q: What can we learn about the woman from...
A.
She isn't ready to cooperate with the man.
B.
She's surprised the man chose her.
C.
She doesn't understand why the man didn't work.
D.
She thinks it's difficult to find a partner.
【简答题】试论述单晶硅与多晶硅的区别与各自的优点和缺点。
【简答题】分光光度法入射光的波长应根据吸收光谱曲线以选择__________为宜,这是因为__________和__________。吸光光度在0.2~0.7时测量的准确度较高,如果不在此范围可以通过__________和__________的方法来解决。欲测定纯钴中微量锰,将试样溶解,锰氧化为MnO4-后比色测定时,应选择__________溶液作参比溶液。