电压源提供确定的电压，与流过电流的大小和方向无关。
查看答案
电流源与电阻并联之后，向外提供的电流不再是确定值，输出电流要随着输出电压的增加而增加。
A. 对
B. 错
What do you think is the intended meaning of Sophie's invitation based on this scenario?
A. It was a real invitation, but she may have forgotten it.
B. It was not a real invitation, but it served as a hint to close the conversation before she left the party.
C. It was not a real invitation, but it functioned as a polite way to end the conversation.
D. It was not a real invitation, but English speakers understand what it means.
How did the Chinese teacher interpret Sophie's invitation based on this scenario?
A. Mr. Xie interpreted the invitation expression as a real invitation so he took it seriously.
B. Mr. Xie interpreted what this invitation statement meant literally.
C. Mr. Xie knew it was not an invitation.
D. Mr. Xie did not interpret the invitation expression as a real invitation.
真空干燥的优点是 （）。
A. 省钱
B. 干燥速率缓慢
C. 能避免物料发生不利反应
D. 能避免表面硬化
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