【多选题】DC/DC变换是将固定的直流电压变换成可变的直流电压,也称为直流斩波,其具体电路主要由以下几类()
C.
BuCk-Boost电路——降压或升压斩波器
【单选题】If there is anything wrong with the sentence, please ____.
【多选题】2020年6月4日,甲公司购进一栋办公楼并于当月投入使用,6月25日,纳税人取得该大楼的增值税专用发票并认证相符,专用发票注明的价款为800 000元,增值税进项税额为72 000元,款项已用银行存款支付,不考虑其他相关因素。下列说法中正确的是( )。
【单选题】If there is anything you need, please don ’ t hesitate to ask.
【简答题】a.If there is anything we can do to help you, we shall be more than pleased to do so. b.We spare no efforts in endeavoring to be of service to you. c.We shall be very glad to handle for you at very lo...
【判断题】升压斩波电路也称 为 boost 变换器。