若两个角的度数之比为8:7,度数之差为10°,则这两个角的度数分别为[ ]
A.80°,70°
B.60°,70°
C.70°,90°
D.85°,75°
答案:A
Attention, please! I have ______ important to tell you. [ ]
A. nothing
B. anything
C. something
球阀的类别是按其结构来区分的,一般分为()球阀和固定球阀两类
A.活动
B.浮动
C.移动
D.转动