How many rulers can you see? [ ]
A. I have three
B. I can see three
C. I like three
答案:B
原料缓冲罐和注水罐压控气源是()
A.氮气
B.瓦斯
C.自压
Excel下面()属于水平对齐方式。
A.左对齐
B.右对齐
C.垂直对齐
D.居中对齐