【单选题】同一方向的用户引入线最多不超过()超过时应改用塑料电缆引入。
【判断题】常见的国际通用域名后缀中.edu代表商业公司。
【单选题】步进电动机在高频区工作产生失步的原因是()。
【单选题】A software requirements specification is that () .
A.
a rough list of things that the proposed software ought to do
B.
a precise list of things that the proposed software ought to do
C.
a formal list of things that the proposed software must do
D.
an estimate of the resouroes (time, money, personnel, etc) which will be required to construct the proposed software
【单选题】肺淤血时肺泡腔中出现胞质内含有含铁血黄素颗粒的巨噬细胞称为
【单选题】.org通常用于哪一类型网站的域名后缀。
【单选题】对称星型连接的三相电源,已知UA=100∠60 则UB=( )