要使三极管处于放大状态，发射结必须（），集电结必须（）。
参考答案：正偏；反偏
慢性肺源性心脏病心胸比率小于正常的原因是（）
A.肺纤维化
B.肺气肿
C.膈肌麻痹
D.肺动脉高压
E.肺淤血
Which description about Hilary Clinton is not true according to the passage ().
A.The former First Lady.
B.The front runner of the republic nomination.
C.The front runner of the democratic nomination.
D.New York senator.
