【简答题】3 What does Mark Zuckerberg think of mistakes and
failure in life?A. Mistakes feed on themselves and lead to failure. B. Any possible mistakes should be avoided to make things perfect. C. Silly mis...
【判断题】在模拟调制系统中,门限效应是指解调器的输入信噪比小于门限值时,输出信噪比急剧恶化的现象。
【单选题】两电阻相并联,已知R 1 /R 2 =1/2,则流入电阻的电流之比I 1 /I 2 、功率之比P 1 /P 2 分别是[ ]。
A.
I 1 /I 2 =2, P 1 /P 2 =2
B.
I 1 /I 2 =2,P 1 /P 2 =4
C.
I 1 /I 2 =1/2,P 1 /P 2 =1/2
D.
I 1 /I 2 =2, P 1 /P 2 =1/4
【多选题】Z7~54.控制按钮应根据使用场合环境条件的好坏分别选用( )。