在外加电压的作用下,P 型半导体中的电流主要是( )。
查看答案
在杂质半导体中多子的数量与( )有关。
A. 掺杂浓度
B. 温度
What is the full name of IOC?
A. International Organization Community
B. Intellectual Orientation Council
C. International Olympic Committee
D. International Olympic Community
In which year will China host the Winter Games?
A. 2020
B. 2021
C. 2022
D. 2023
How many sizes for basketball officially?
A. 2
B. 3
C. 4
D. 5