单相全波整流电路的每支管子所承受的最大反向电压（）单相桥整流电路的每支管子所承受的最大反向电压。
A、大于
B、小于
C、等于
参考答案：A
下列属侵袭性胸腺瘤特点的是（）
A.包膜不完整
B.可引起胸腔积液
C.可引起心包积液
D.可囊变
E.含有大量脂肪成分
Questions 11 to 18 are based on the conversation you have just heard
A．The shipping company.
B．The firm dealing with documents.
C．The travel firm.
D．The firm with a lot of people.
