题目内容

Listen to the passage and decide whether the statements are true (T) or false (F).[音频]1) The speaker suggests that we do spring cleaning because spring is the only season suitable for tidying up rooms.2) It is hard for some people to do spring cleaning since they are sentimental about letting go of their personal property.3) The speaker is anti stuff and suggests that people should not buy new things.4) According to the speaker, brand-name objects can’t make others admire you though they can make you happy.5) What the speaker cannot give up is her CD collection and childhood teddy bear.

查看答案
更多问题

工频逆变器的频率范围是_______Hz。

A. 20~30
B. 30~40
C. 50~60
D. 40~50

含有大量的高次谐波的输出波形是______。

A. 方波
B. 阶梯波
C. 正弦波
D. 园波

逆变器的输出电压的波形为_______时,失真度低。

A. 方波
B. 尖波
C. 正弦波
D. 阶梯波

下列只有单个MPPT的逆变器是________。

A. 集中型逆变器
B. 独立逆变器
C. 组串型逆变器
D. 微型逆变器

答案查题题库