PCB的尺寸是在Top over Layer层面上用线绘制出一个多边形。
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Altium Designer中,与工程无关的文件被称为“自由文档”。
A. 对
B. 错
The modern automobile is made up of _______ basic sections: engine, chassis, body and electrical equipment.
The engine acts as the power unit located normally at the ______ of the car.
The engine is the ________ of an automobile .
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