He's my ____________. He likes science. [ ]
A. sister
B. mother
C. brother
答案:C
JComponent的直接父类是( )。
A. I=4x=5
B. I=7x=15
C. I=6x=8
D. I=10x=7
根据清洗零部件不同的精度要求如何选用清洗工具?