雷达液位计不适用于测量什么介质液位()
A.高温
B.高压
C.易燃易爆
D.低温
参考答案:D
(71) , the brains of a computer, it contains the ALU, the clock, many registers, the bus interface, and circuitry that makes these pans work together.
A. I/O device B. CPUC. Memory D. Operating system
X线管内保持高度真空的目的()
A.保护灯丝
B.保护靶面
C.形成高压回路
D.防止电子与空气分子冲击而减速
E.以上都不是