现场校验时,频率对额定值的偏差不应超过()。
A.±2%
B.±3%
C.±4%
D.±5%
参考答案:D
If you are weak a subject, and asking a teacher for advice can help. [ ]
A. at; working
B. in; work hard
C. at; work hard
D. in; working hard
继续推进优势农产品区域布局是()的必然选择
A、发展现代服务业
B、发展现代农业
C、发展现代畜牧业
D、发展现代种养业