调频器和鉴频器从原理上说都属于频率-电压变换器件。
查看答案
脉冲计数式鉴频器是一种直接鉴频器。
A. 对
B. 错
请写出以下颜色的象征寓意红色——黄色——蓝色——绿色——白色——紫色——品红——黑色——
What did Cliff Young do in his life?
A. He took part in the 875-kilometer Australian marathon in 1983.
B. He gave all his first prize to five other runners.
C. He participated in many races and won a number of them.
D. He raised money for homeless children.
精力旺盛、表里如一、刚强、易感情用事,是( )气质类型的特点。
A. 胆汁质
B. 多血质
C. 黏液质
D. 抑郁质
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