问题
选择题
You ________ come tomorrow. I can do it myself. [ ]
A. needn't
B. mustn't
C. can't
D. shouldn't
答案
答案：A
搜题请搜索小程序“爱下问搜题”
You ________ come tomorrow. I can do it myself. [ ]
A. needn't
B. mustn't
C. can't
D. shouldn't
答案：A
。求所示单管放大电路的电压放大倍数
及放大电路的输入电阻Ri分别为（）。
