【判断题】晶体三极管本质上是一个电流控制电流源器件。
【单选题】下列说法中不正确的是( )
D.
稳压二极管在稳压状态时,它的PN结处在反向击穿状态
【判断题】心尖部第一心音增强并呈拍击样,主要见于二尖瓣狭窄。( )
【判断题】虚拟人机工程学设计是借助虚拟样机(Virtual prototype)系统。
【单选题】A good artist, like a good engineer, learns as much from ________ his success.
【单选题】John was good at his work and he was ()to general manager in his company.
【单选题】A good manager identifies the interest of his employees _____ his own .