5÷7的商用分数表示是( ),用循环小数表示是( ),用精确到0.01的小数表示是( )。
;;0.71
What does your mother do?[ ]
A. She is a teacher.
B. I am a teacher.
C. He is teacher.
电测量指示仪表的测量机构必须具备哪几个基本功能?